Space warfare or space combat was the use of armed starships and other spacecraft for the purposes of military actions across star systems and the galaxy. Along with ground warfare and starfighter combat, by 0 BBY space warfare was one of three most significant branches of warfighting. Evolving from water navy engagements and in turn the earliest orbital battles, space warfare became a high technology affair that often defined the outcome of the galaxy's most important conflicts.
Turbolasers were the primary form of capital ship armament for thousands of years.
Technological innovation determined the design of warships and naval doctrine and the outcome of battles. While the sizes and capabilities of starships varied, four main technologies drove and were advanced by space warfare: weapon systems, shield technology, sublight propulsion, and hyperdrive technology.
There were two basic types of space weaponry: energy and conventional. Energy weapons began with microwave lasers for offense and were typically secondary to conventional, physical weapons. From 4000 BBY however, energy weapons were the dominant form of weaponry in space combat, dominated by the turbolaser and the laser cannon, outgrowths of blaster technology that had matured at the same time. On capital ships, energy weapons were normally grouped into batteries based upon the weapon type and its placement upon the hull. For example, on an Imperial-class Star Destroyer the heavy turbolasers on the portside of the hull's dorsal surface would be grouped into one battery, while those on the starboard dorsal surface would be grouped into a second battery. Targeting computers in capital ships were usually shared between the weapons of each battery, allowing the gunners to concentrate their fire on particular targets. Other designs of energy weapon included the charric, a Chiss advancement of early microwave lasers; the ion cannon, an electromagnetic weapon used to non-destructively disable electronic systems; and the superlaser, a Clone Wars development that was an immensely more-powerful design of laser that could cause planetary-scale damage.
Conventional weapons were the first weapons used in space combat. Although the first conventional space weaponry included projectiles such as slugs, technology further progressed and came to encompass guided missiles and torpedo launchers. Conventional weapons could be guided, as in the case of missiles, or unguided, as in the case of bombs. Conventional weapons came to include the nuclear bomb, the proton bomb, proton torpedo, and the concussion missile.
A deflector shield envelops a Naboo starfighter.
Deflector shields were a critical component in starship design and were used to mitigate damage from impacts. They included ray shields, which protected against energy weapons, and particle shields, which repelled physical objects. Both types consumed large amounts of energy and for a long period in galactic history, were reserved for only the largest warships with the greatest power-generating capability. Early warship captains therefore thought in terms of armor for defense. Other early defenses included charged particle clouds to diffuse energy weapons and hulls treated with kiirium to reflect beams.
A refinement of the squintpipe process in the 7500s BBY produced shields that were stronger and quicker to regenerate, and also reduced the effective size of deflector shield generators. From then on, reliable deflector shields could be fitted to ships of all sizes. Other defenses included point-defense cannons, which were designed to destroy incoming threats like torpedoes before they could hit the ship.
In spite of the necessary elements of deflector shields in starship designs, not all ships incorporate them. A notable example of ships lacking deflector shields are the TIE-series starfighters, in particular the TIE/LN starfighter, which was not included alongside life-support systems because Imperial doctrine dictated that their usage among fighter pilots was a sign of cowardice.
Sublight drives propelled ships below the speed of light and were best represented by ion drives: powered by fusion generators, these engines expelled particles at a very high speed to provide propulsive force. Sublight engines determined speed and maneuverability and could prove decisive: the Galactic Empire's TIE/LN starfighter used an extremely efficient twin ion engine design and stripped-down spaceframe to improve its mobility. The Alliance to Restore the Republic countered this with the faster and more maneuverable RZ-1 A-wing interceptor, which the Empire countered in turn with the even faster TIE/IN interceptor.
Hyperdrive technology was an enormous influence on strategy in space warfare: fleets travelling faster-than-light in hyperspace had to traverse known hyperlanes to avoid dangerous mass shadows. For much of galactic history, starships lacked the computing power to calculate safe routes between systems and were confined to jumps within networks of jump beacons. In war this allowed navies to effectively pin ships at a certain point by disabling its beacon. By 4100 BBY, navigation computers had advanced to the point that jump beacons were no longer needed, making control of routes more difficult, as blockading one route merely pushed ships to one of many alternative ones. However, statistically speaking, only a few of these route could be traversed quickly, and a military force that controlled the fast routes could rapidly redeploy to intercept an adversary using the slow ones. Hyperlanes thus determined the strategic geography of space warfare, and fleets repeatedly battled over the same planets on significant hyperspace routes, such as Chazwa, or planets at hyperlane junctions such as Yag'Dhul or Brentaal IV. Militaries might also maintain secret hyperlanes to get the drop on their enemies: during the Clone Wars, General Grievous made use of a secret route through the Deep Core to directly attack Coruscant, while the Galactic Republic and the CIS negotiated with the Hutts for control of the Nexus Route connecting each other's core territories. The Rebel Alliance also made use of secret Claatuvac Guild routes supplied to them by Chewbacca for hit-and-hype raiding against the Empire.
Ships designed for war were typically split into two broad classes: starfighters and capital ships.
An X-wing and TIE Interceptor in head-to-head combat
Starfighters were small craft typically piloted by one or two beings. Their operations and role encompassed an entire doctrine and form of warfare in its own right, known as starfighter combat. Types included space superiority fighters, bombers, and snubfighters. Space superiority fighters were stripped-down ships, usually minimally armed and armored, and were used to combat enemy bombers but typically could not attack capital ships. Bombers were more heavily-armed starfighters and were usually equipped with bombs, torpedoes and missiles so that they could make bombing runs on enemy warships. They were typically less-maneuverable than space superiority fighters and usually required their own fighter escort to avoid being shot down.
Snubfighters sat between space superiority fighters and bombers in size and armament and were designed to both dogfight with other fighters and attack capital ships. Though snubfighters like the Rebel X-wing and Y-wing became famous, for the majority of galactic history snubfighters were not heavily used in deep-space combat: commanders considered it better to operate snubfighters from planet-based surface airfields to strike through cloud cover and launch torpedo strikes and strafing runs against attacking ships and troop transports. However, the advantages of snubfighters tended to disappear in the great ranges between opposing fleets and their payloads were not as great as dedicated bombers. It was only after the success of N-1 starfighters against Trade Federation battleships at the Battle of Naboo in 32 BBY, an experience confirmed by the role of Y-wings against the Malevolence at the Battle of the Kaliida Nebula during the Clone Wars, that the snubfighter began to be taken seriously as a deep-space battleship killer.
Starfighters may or may not have had a hyperdrive; if not, they were often launched from a carrier or other larger craft. Some, like Imperial TIE/LN starfighters, were armed only for fighter-on-fighter combat; more versatile ones, like the Rebel X-wing and Y-wing snubfighters, were also capable of anti-ship and anti-surface attacks. Bombers like the TIE/sa bomber and the A/SF-01 B-wing starfighters were typically poor dogfighters and relied on heavy shielding or escorts to push through fighter screens and attack warships.
By nature, a starfighter was intended to be small, fast and agile, designed to operate either on its own or as part of a squadron or a fighter wing on a variety of mission profiles, ranging from escort duty to reconnaissance missions and full-scale assault. Due to their size, starfighters could not engage in self-sufficient operations for any long period of time, needing a base of operations to provide fuel, repairs and supplies for the pilot, given as these cannot be carried aboard in any large quantity.
A dizzying variety of capital ship classifications existed throughout galactic history. However, all agreed that a capital ship was a military starship that was at least one hundred meters in length. After the Clone Wars, the most common classification system was the Anaxes War College System, which replaced the system instituted after the Ruusan Reformation. The largest class recognized by that system was the cruiser, reflecting the Ruusan Reformation's restriction on transgalactic warships larger than six hundred meters. By the time the Clone Wars broke out, many rich sectors had commissioned much larger warships with local-range hyperdrives for their defense, with lengths of several kilometers and making the cruiser an increasingly-meaningless class.
An Imperial-class Star Destroyer and Mon Calamari cruiser engage each other at point-blank range
Under the Anaxes War College System, ships smaller than one hundred meters were classified as either starfighters, or if they were unarmed, space transports. Mindful of what had happened to the cruiser class, the Anaxes architects extended their classification system to account for the possibility of truly gigantic warships. Corvettes were fast, light attack ships which were used in a variety of roles, including blockade running, anti-starfighter missions, or escort and support for larger ships. Frigates sat between two hundred and four hundred meters and served the purpose of eliminating smaller vessels of an enemy fleet and often carried their own starfighter squadrons. Cruisers were from four hundred to six hundred meters in length and were heavily armed relative to their size and could often trade blows with much larger ships. Heavy cruisers were from six hundred to one thousand meters in length and were typically the backbone of any fleet engagement. Star Destroyers were between one and two kilometers in length and were typically the most numerous large starship, specializing in heavy ship-to-ship combat. Battlecruisers were from two to five kilometers in length and were heavily armed, designed for long-range, independent operations hunting down other capital ships. Finally, dreadnoughts were ships over five kilometers in length and so powerful that the mere threat of their deployment could pacify multiple sectors. Although not an official class, there was also a designation known as superdreadnaught, which included the Star of Coruscant and the Eye of Palpatine during the Great Galactic War and the Galactic Civil War, respectively, with the implication being that the ships were far larger in size and more powerful than an ordinary dreadnought.
Additionally, the Anaxes War College System carried a shorthand for use during engagements, one that lumped warships of different classes based on their size and capability. Corvettes, space transports and starships acting as warships in-theater were designated as gunships, small, fast, heavily-armed ships that specialized in destroying the maximum number of small enemy ships in a space battle and relied on evasion far more than their shields to escape damage. Frigates and lighter cruisers - the workhorses of most military engagements - were identified as cruisers. Big ships of the line whose mere presence could change the course of a battle were referred to as battleships.
In addition, some capital ships had been developed specifically to both revolutionize space warfare as well as ensure dominance for an extended period of time. A notable example of these ships were the Eclipse-class dreadnought and the Sovereign-class Super Star Destroyers developed by the Galactic Empire, and more specifically by the Imperial Navy.
A Thanium star-glaive of Xim's empire.
Much information surrounding the very earliest wars in space was lost by the era of the Galactic Civil War, but the legends of the eldest spacefaring civilizations all told an intriguingly similar story – of a terrible war waged with unimaginable weapons. Such early conflicts included the genocidal war between the Celestials and the Rakata, followed by the savage conquests of the Infinite Empire.
In recorded history, starships were first armed as a response to natural hazards: deflector shields were necessary to protected crews and passengers from radiation or micrometeoroids, while ship-mounted laser weapons and missiles were developed in response to rogue asteroids or destructive space-borne creatures. Inevitably, this proliferation of weapons brought space warfare along with space travel. The first well-documented wars were those of the Tionese and the Hutts. Tionese warships used guided missiles, torpedo launchers and microwave lasers for offense. Protection was provided by point-defense missiles, clouds of charged particles to diffuse energy weapons, and thin armor plating coated with superconducting, mirror-bright kiirium alloy to reflect laser attacks.
In this era, ships larger than light cruisers were rare: the flagship of Xim the Despot, the Eibon Scimitar, was considered gargantuan in its time, but military historians during the Imperial Period generally agreed that it would be considered a heavy cruiser at best under the Anaxes War College System. Wars in this era were fought across networks of jump beacons. Significant conflicts of this early era of space warfare included the Cronese Sweeps, the Expansionist Wars of Xim's empire, Xim's final war with the Hutt Empire, and the Unification Wars that founded the Galactic Republic.
The Tionese War did not see a shift towards larger warships: such ships were expensive to build and of little strategic use against fleets of cheaper and more nimble craft. Alsakan's Atgeir-class battlecruisers – renowned for their supposedly impregnable shields – were exceptions to the rule. During the early Alsakan Conflicts, ships like these battlecruisers and Coruscant's Gilagimar were chiefly used for home defense while fleets of swift cruisers launched raids and protected colonies in the Exploitation Region. The best example of this was Admiral Hirken's Northern Dependencies campaign during the Fifth Alsakan Conflict.
Admiral Hirken's defense of the Northern Dependencies during the Fifth Alsakan Conflict.
Jump beacons were still essential for hyperspace travel, which allowed the Bureau of Ships and Services to halt the First Alsakan Conflict of 17,018-16,700 BBY by threatening to withhold navigational data from both Coruscant and Alsakan. In 10,966 BBY, BoSS was also able to end the Pius Dea Civil War by infecting the ships of the Pius Dea Faithful with rogue navicomputer codes that scattered their fleet and left what remained to be easily overwhelmed by a combined Jedi-Renunciate fleet at the Battle of Uquine.
After the Duinuogwuin Contention of 15,500 BBY, the Republic encountered few opponents with large warships and so had little use for large capital ships. The Republic Navy preferred fast gunships that could escort merchant transports and colony ships. The Pius Dea Crusades of 12,000-11,000 BBY saw the use of cathedral ships and large, armored men-o-war optimised for broadside combat, but the next widespread use of large capital ships came around 10,000 BBY when the Republic was briefly provoked by the rise of the Kumauri Empire. Vall Kumauri's massive battleships were armed with mass-driver cannons capable of accelerating asteroids to planet-cracking velocities (similar to ancient Hutt planechanga). The Republic countered with an identical fleet, which cowed or destroyed several hostile civilizations during the Republic's expansion and even served as terror weapons during the Osara Mundicide of the Tenth Alsakan Conflict. Advances in planetary shields largely eliminated the threat of bombardment, but the Kumauri Empire's most enduring innovation was the use of synthetic madilon to make smaller, more efficient hyperdrives that allowed longer jumps across the galaxy's network of jump beacons.
The Waymancy Storm, a furious confrontation between the Galactic Republic and Signatories of Waymancy in 7811 BBY, sparked the next major wave of naval innovation. In the first battles, Republic ships were torn apart by rapid fusillades of laserfire: Waymancy's Sisters of the Machinesmith had developed the Sif-Alulan process and produced extremely efficient power generators that allowed for energy weapons far more powerful and with much faster rates than anything the Republic could bring to bear. Waymancy was defeated after the Sif-Alulan process was reverse engineered, allowing the Republic to create its own pulse-wave cannons and deflector shields. The process was further improved upon by by the Verpine crafter Lyns Skutroo, who created the squintpipe process in the 7700s BBY. This created a brief period in which rapid-fire turbolasers outclassed all available defenses. This caused naval tacticians to disdain capital ships in favor of swarms of gunships that could overwhelm opponents. Since deflector shields were now useless, this led to a search for stronger hull armor, with vacierite replacing kiirium. In the 7500s BBY, further refinements of the squintpipe process produced shields that were stronger and quicker to regenerate, and shield generators became small enough to be fitted to starships of any size.
The refined squintpipe process sparked a golden age of warship construction. Capital ships reemerged as the primary warships of the Republic Military, its Planetary Security Forces, and its enemies, the worst of whom were the Sith. In the Great Hyperspace War of 5000 BBY, the Republic faced a fleet of massive Sith Derriphan-class battleships led by Naga Sadow's Corsair. The Republic Navy countered with ever-larger capital ships, including command ships, battleships, and the Hammerhead-class cruiser (one of the most enduring warship designs in galactic history, which remained in military service with upgrades for nearly 3,000 years)
Hammerhead-class frigates at the Battle of Vanquo.
The double threats of the Sith and the Mandalorians in what became known as the Old Sith Wars prompted the Republic to build ever-larger, more powerful ships, culminating in titanic clashes between the largest warships yet seen in the galaxy. These included the 3,100-meter Inexpugnable-class tactical command ship, the 1,200-meter Centurion-class battlecruiser, and the 600-meter Interdictor-class cruiser. This cruiser design projected a simulated gravity well into realspace, creating a mass shadow in hyperspace that prevented hyperspace jumps or dragged ships back into realspace. However, this innovation would soon be rendered ineffective by better hyperspace sensor suites and multiphase null field units, and it was not until the Galactic Civil War that gravity well projectors became decisive weapons again. The Great Galactic War, Cold War and Galactic War saw Republic Valor-class cruisers and even the "superdreadnaught" Star of Coruscant fighting the Terminus-class destroyers and Harrower-class dreadnoughts of the Imperial Navy of the restored Sith Empire.
By 4100 BBY, the era of the jump beacon was coming to its end as more effective and powerful navigation computers were developed. Wary of rumblings beyond the Republic frontier, the Republic Navy conducted crash research to ensure that its ships could cross the galaxy quickly and safely without having to rely on beacons. This was a prescient move: during the Great Sith War and the Mandalorian Wars, the Republic Navy destroyed many jump beacons in an effort to deny its enemies easy passage into Republic space.
Technological innovation slowly obsoleted battleships, however: the Seventeenth and final Alsakan Conflict was caused by Alsakan maintaining and expanding its fleet despite the conclusion of the Galactic Wars. The Republic responded by building a fleet of two-kilometer-long Invincible-class fast battleships. Alsakan and the Axis' response was mass-produced squadrons of sublight missile corvettes, which successfully defended their systems from Republic raids. However, Corellia reacted with a fleet of long-range frigates. Technological breakthroughs enabled them to be outfitted with fast engines, strong shields, and heavy turbolasers, allowing Prince-Admiral Jonash e Solo to rapidly outfight both Coruscanti and Alsakani battleships and forcing a peace treaty on both.
The battleship era ended in the 2500s BBY owing to economic concerns. Tacticians once again came to prefer fleets of smaller cruisers, most notably the striking fleet of wroshyr-framed wooden gunships led by the Jedi Lord Valenthyne Farfalla aboard the Fairwind in the New Sith Wars. The Ruusan Reformation of 1000 BBY halted large battleship construction: not only was the Republic Navy dismantled and responsibility for defense given to the Planetary Security Forces and the Judicial Forces, but the size of ships was capped at the six-hundred meter cruiser. Ships larger than six hundred meters had their hyperdrives limited and their navicomputers restricted to local charts. For centuries after Ruusan, capital ships larger than light cruisers were rare and were seen as extravagant.
Cruisers emerged as the workhorses of the PSFs and the Judicials alike, and they served well in the Unification Campaigns after the New Sith Wars. However, as the Republic's authority in the Outer Rim Territories slowly crumbled in the final centuries of the Great Peace of the Republic, wealthy industrial sectors began building new capital ships for the sector fleets, while megacorps like the Trade Federation took advantage of loopholes in the law to develop their own trade defense fleets. These developments culminated in giant cruisers on a scale not seen for millennia, with rich planets like Kuat and Rendili seeking to create impregnable defenses and impress their neighbors. Additionally, shipwrights were granted exemptions to allow them to pursue technological innovations and showcase prototype designs. This resulted in corporate "demonstration fleets" made up of variations on warship design, which were often leased to sectors that could afford them. By the 30s BBY, rich sectors were awash with massive warships, with their fleets' numbers swelled by loans from starship manufacturers. Meanwhile, the defense limits of the Ruusan Reformations meant that poor Rim sectors struggled to police their worlds and defeat smugglers and pirates with undersized fleets of underpowered warships.
The Republic and Confederate Navies clash at the Battle of Coruscant.
The Clone Wars of 22 to 19 BBY, a product of the Order of the Sith Lords' Grand Plan to seize control of the galaxy, fundamentally changed the conduct of space warfare. Most significantly, it resulted in the spread of three new enormous variations of capital ship: the Star Destroyer, the Battlecruiser, and the Star Dreadnought. Even prior to the Ruusan Reformation, ships larger than two kilometers in length had been rare, and most warships tended to be below the one-kilometer mark. However, the Clone Wars saw the rapid development and widespread use of Star Destroyers. While the name had originally been a corporate marque of Kuat Drive Yards, it came to refer to a ship in excess of one kilometer long, carrying an armament powerful enough to lay waste to entire star systems. Star Destroyers, exemplified by the Venator-, Victory-, and finally the Imperial-class, would become the backbone of battle fleets during and after the Clone Wars. The Separatists' answer to the Star Destroyer was the Providence-class carrier/destroyer, but though the class was made famous by General Grievous' Invisible Hand, there were relatively few of them.
An even larger development of capital ship was the battlecruiser, massive, heavily armored warships designed to hunt down and destroy other capital ships in long-range, independent operations. The first warship that gained formal recognition as a battlecruiser was KDY's 2.5-kilometer Procurator, which served as a template for a series of ever-larger KDY battleships. By the time of the Clone Wars, dozens of battlecruisers defended Core and Colonies sectors, among the Procurator's refinement, the four-thousand-meter Praetor-class. The majority of these huge ships went into Republic service during the Clone Wars, with most serving as local defense against Separatist incursions. Others were uparmored, fitted with transgalactic-capable hyperdrives and became the spearpoints of task forces sent against key Separatist worlds, most notably and tragically the Quaestor at Pammant. The Confederacy of Independent Systems maintained a few ships that could be called battlecruisers, most notably the Subjugator-class, best represented by the Malevolence, but they preferred fleets of smaller frigates and light destroyers. The Galactic Empire would commission relatively few battlecruisers, relegating them to Core defense, and saw them as being less versatile than Star Destroyers but not instilling the same terror as dreadnoughts.
New instruments of naval power: Battlecruisers, Star Destroyers and a Star Dreadnought refuelling.
The star dreadnoughts were the largest class of capital ship ever built, and were massive warships designed to be so powerful that the mere threat of their deployment would pacify multiple sectors. The first warship considered a dreadnought was KDY's eight-kilometer Mandator, built twenty years before the Clone Wars. It triggered a race among wealthy sectors for similar warships, and during the Clone Wars, KDY developed the improved Mandator II design. The Galactic Empire continued star dreadnought development, culminating in the Sarlacc Project and the Executor-class star dreadnought, a 19-kilometer-long battleship so large and powerful that it was nearly invincible in fleet combat. Many in the Imperial Navy, however, came to disdain star dreadnoughts as inefficient compared to fleets of smaller cruisers for patrolling the galaxy, and derisively referred to them as "Super Star Destroyers."
The Republic Navy was opposed by the Confederate Navy, which compensated for the relative fragility of their Recusant-class light destroyers and Munificent-class star frigates with huge numbers of the droid-crewed vessels, as well as immense swarms of starfighters. In addition to traditional interceptors like the Belbullab-22 and the droid tri-fighter, and bombers like the Hyena-class and Belbullab-24, the Separatists also operated large numbers of snubfighters. In a departure from traditional doctrine, the Confederate Navy would often deploy squadrons of snubfighters like the Vulture-class droid starfighter in both a dogfighting an an anti-ship role. Developments in snubfighter technology had outraced doctrine. The performance of N-1 starfighters at the Battle of Naboo had shown the Separatists that hyperspace-capable snubfighters could indeed destroy battleships. The experience was confirmed with the destruction of the Separatist superweapon Malevolence at the Battle of the Kaliida Nebula, helped in no small part by it being crippled by Y-wing starfighters. The Republic Navy was not slow to notice this. Its main starfighter carriers of the war, the Venator- and Victory-class Star Destroyers, were originally designed with traditional doctrine in mind and to operate NTB-630 torpedo bombers in an anti-capital ship role, alongside short-range A-6 Interceptors for escort and dealing with enemy starfighters. By the end of the Clone Wars, carrier capacity was largely given over to snubfighters like the ARC-170, and designers like Vors Voorhorian and Walex Blissex spent the war years designing a new generation of snubfighters that could dogfight on equal terms with any starfighter in space.
The Confederacy of Independent Systems fought the Republic with a stateless strategy, making surgical strikes and terror raids designed to deny the Republic key invasion corridors, undermine support for the war, and sever key fleets' supply lines. The sheer size of Republic territory meant that it was impossible for the Republic Navy to repel all the raids, and if it tried to take the offensive against the Separatists, it might leave key worlds vulnerable. The Republic never found a solution to this strategy. Instead, it outgrew it, conscripting vast numbers of new crews and cloning huge numbers of new clone troopers, and by the third year of the war, had committed a substantial portion of its much larger industrial base to produce a fleet so large it could both defend its territories and take the fight to the Separatists. The Separatists' Outer Rim holdings were ground down in an attritional campaign known as the Outer Rim Sieges. After the Separatist Droid Army was finally deactivated, the new Galactic Empire inherited the immense Republic Military and both the Republic and the Confederacy's military-industrial complexes, allowing Emperor Palpatine to consolidate control over the galaxy with a new navy larger than anything ever seen before.
The Galactic Civil War of 2 BBY-19 ABY cemented the role of the Star Destroyer as the central warship of navies. Under Emperor Palpatine, the Planetary Security Forces were nationalized and merged into the Sector Groups, massive concentrations of fleet power at the sector level. Distrusting local loyalties, these fleets were rapidly filled with new ships loyal to Imperial Center (decommissioned PSF equipment and ships would later become a major source of resources for the Rebellion) The Imperial Navy ultimately expanded to become the largest military starfleet the galaxy had ever seen, peaking at 25,000 Star Destroyers and millions more smaller ships.
Forces of the Rebel Alliance and Galactic Empire engage each other in Corellian space
The Imperial Navy's doctrine emphasised maximizing capital ship firepower rather than achieving starfighter superiority, and it subordinated its starfighters to this role. As such, the Republic Starfighter Corps, when reorganized into the Starfighter Corps of the Galactic Empire, was reduced to being dependent on the Imperial Navy. The large carrier capacity of the Venator-class Star Destroyer was done away with in future designs in favor of smaller fighter complements. This made room for bigger, more powerful reactors, allowing them to be more heavily armored and carry stronger shields and more powerful weapons, all of which would make starfighters less effective. The new Imperial-class Star Destroyer became the backbone of the Imperial Starfleet and was heavily optimised for fleet combat, carrying only a single wing of 72 starfighters, relatively small in comparison to the Venator-class' 420 fighters. The Imperial Navy's general strategies and functions included blockading ports in order to prevent supplies from reaching a planet to cripple its ability to fight; bombarding planets in order to annihilate its infrastructure; and transporting other branches of the Imperial military to their destination as well as supplying them with space and aerial support after disembarking.
Seeing it as a legacy of the Separatists, the Imperial Navy abandoned snubfighters in favor of more traditional starfighters: the TIE Series, exemplifying traditional starfighter doctrine with the TIE/LN Line Starfighter and the TIE/sa Bomber, was a series of barebones fighter designs built around a ball-shaped cockpit and the revolutionary twin ion engine design. Seen as complements to Star Destroyers, they served as escorts, scouts, hit-and-fade raiders, and bombers supporting ground troops. As such, they lacked hyperdrives, deflector shields, or even life support systems, reducing their mass and giving them great speed and maneuverability, but also limiting their survivability and their range. The Imperials also chose to eliminate shielding and life-support systems specifically because they viewed the use of such by their TIE pilots as cowardice. In addition, as a holdover towards the Galactic Republic's use of cloned soldiers and pilots during the Clone Wars and their treatment of the clones as living droids, the TIE pilots were also given a notoriously low amount of protection during battle and even during training exercises, even when Imperial officers requested that they make accommodations for the growing amount of human pilots that graduated from the Imperial Academy system, which resulted in the TIE fighter being a symbol for the Empire's callous disregard of its own troops.
The Clone Wars had stimulated aggressive new research into interdiction field technology, and the Empire built on the Republic's developments. New designs of gravity well projector were powerful enough to pull any ship out of hyperspace or to pin it in realspace. However, only large capital ship had the spaceframe and drive systems to carry the large, bulbous generators, and Immobilizer 418 cruisers became common sights in Imperial fleets. They were decisive in preventing the immediate escape of the Alliance Fleet into hyperspace at the Battle of Endor. Owing to their role, however, these cruisers were underpowered for their size, and only large battleships like the Sovereign-class and Eclipse-class dreadnoughts were big enough to carry effective interdictor systems without serious penalties in weaponry.
The Galactic Empire was opposed by the Alliance to Restore the Republic, which operated on an entirely different military philosophy. Since it lacked large numbers of capital ships, the Rebel Alliance made heavy use of snubfighters as part of its stateless strategy. Powerful starfighters like the T-65 X-wing conducted hit-and-hype raids against prominent Imperial targets and supply convoys, using their superior shielding, armament, and hyperdrives to inflict disproportionate damage on Imperial targets. Meanwhile, the Alliance Fleet would roam the galaxy, challenging Imperial authority merely by existing, and waiting for the chance of a decisive battle with the Galactic Empire. The Galactic Empire made belated moves to develop their own snubfighters like the TIE Advanced x1 and the TIE/D Defender after the Rebels inflicted humiliating defeats on them with X-wings, but the most numerous new development was the TIE/IN, a non-hyperspace capable traditional interceptor that though capable of outracing Rebel fighters, was not equipped with deflector shields. Only declining numbers of TIE pilots in the years after Emperor Palpatine's death as the Empire lost ground to the New Republic spurred warlords such as Grand Admiral Thrawn to retrofit TIE Interceptors with shields.
The Orinda campaign of 12 ABY reaffirmed the utility of large battleships.
A fourth Imperial influence on space warfare was its increasing resort to superweapons to counteract the Rebels' stateless strategy. The Empire's initial response was a policy of reprisal, a system of state terror that was institutionalised in the Tarkin Doctrine. However, the policy of overwhelming force in an effort to deny the Rebels safe haven did more to foment resistance than eliminate it. The creation of superweapons like the Death Stars, the Eclipse-class dreadnoughts, the Galaxy Gun, and the Sun Crusher, was intended to reverse this state of affairs by introducing the possibility of a reprisal so terrifying - namely, the destruction of entire planets, or even entire star systems - that no world would risk aiding the Rebellion. All these superweapons consumed enormous amounts of resources and more often than not were destroyed early in their lives by concentrated Rebel raids, most notably the Battle of Yavin and the Battle of Endor, by the very snubfighters the Empire had disdained. The risks of using superweapons were such that, at least regarding the Death Stars, their mere usage required both an Imperial Intelligence report as well as explicit authorization from the Emperor and his office to those with oversector authority.
After the destruction of the Second Death Star at the Battle of Endor and the subsequent collapse of Imperial authority, the New Republic moved away from the development of battlecruisers and dreadnoughts: its strategists saw them as obsolete, narrowly-focused on fleet combat, and vulnerable to "trench run disease" - starfighters hugging close to their hulls and using surface trenches for cover to launch strafing runs. Ship design in the Defender and New Class Modernization Programs instead focused on smaller, more versatile, modular ships, as well as a focus on fleet carriers for large starfighter complements. However, the poor performance of the New Republic Defense Fleet against fleets of dreadnoughts in Operation Shadow Hand, and the experience of the Lusankya's duel with the Reaper during the Orinda campaign, forced a change in design philosophy. The Mon Calamari Shipyards subsequently created the 8.5-kilometer Mediator-class battle cruiser and the two massive, 17-kilometer Viscount-class Star Defenders, Bounty and Krakana, intended as the centerpiece of the New Republic's Outer Rim defenses in the aftermath of the Galactic Civil War.
New Republic starfighters engage the Yuuzhan Vong.
The New Republic adopted a military system that was wholly different to that of the Galactic Empire. Unlike the Imperial Navy, which had been focused on invasion and occupation, the New Republic Defense Fleet was focused on peacekeeping, patrolling, and rapid crisis response, working with and alongside Planetary Security Forces rather than absorbing them. To this end, rather than the Imperial Navy's immense number of ships and Sector Groups used to hold down an entire galaxy, the New Republic Navy was smaller and divided into four (later five) large fleets of some five hundred ships each (each roughly the size of an augmented Imperial Sector Group). The four fleets later became permanent regional commands based at Coruscant, Bothawui, Elom, and Kashyyyk. The emphasis was on flexibility, with one battle group in each fleet serving as a mobile reserve which could be reinforced with multi-role task forces to temporarily become a powerful battle fleet.
This system served the Republic well after 12 ABY, blockading and neutralizing the last Imperial holdouts. However, it meant that the New Republic was woefully unprepared for a totally unexpected threat when the Yuuzhan Vong War began in 25 ABY. Extra-galactic alien invaders, the Yuuzhan Vong operated bizarre organic starships and weapons far more powerful than their New Republic equivalents. A single Yaret-Kor plasma cannon (the primary armament of most Yuuzhan Vong ships) aboard a yorik-et (the primary Yuuzhan Vong starfighter analog, nicknamed the "coralskipper" by New Republic pilots) was noted to have greater firepower than all four laser cannons aboard an X-wing starfighter. Nearly all Yuuzhan Vong ships were more heavily armed than their galactic counterparts, though their ability to defend themselves was typically inferior.
Regardless, the New Republic's fleet organization led to it adopting a strategy of husbanding its fleets, guarding the key hyperspace approaches to the Core and Colonies while it built up its forces in preparation for a decisive fleet battle on ground of its own choosing. The strategy was fundamentally based on a perception of what had allowed the Rebel Alliance to decisively defeat the Empire at the Battle of Endor, but it neglected other tactics that had also served the Rebellion, including commerce raiding, pinpoint strikes, and local defense. This made the New Republic appear weak in the early stages of the war, and the obsession with ceding ground in the hopes of luring the Yuuzhan Vong into a decisive engagement meant that great swaths of the galaxy and billions of people were abandoned to the invaders: The Yuuzhan Vong would capture the majority of the territory they would hold during the war in its first year.
Despite a disastrous first two years of the war which culminated in the loss of Coruscant to the Yuuzhan Vong and the near-destruction of Galactic City, the New Republic, reorganized into the Galactic Federation of Free Alliances, at last achieved technological parity with the Yuuzhan Vong. Innovations such as "stutter fire" laser cannons to confuse and overwhelm dovin basal defensive shields and jamming yammosk war coordinators allowed the Galactic Alliance to win more victories, culminating in the Battle of Yuuzhan'tar, where a massive Alliance, Imperial Remnant, Hapan, Chiss and Jedi force descended on occupied Coruscant, killed Supreme Overlord Shimrra and ended the Yuuzhan Vong War.
The immense taxes required for reconstruction in the aftermath of the Yuuzhan Vong War soon provoked resentment across the sectors, while others, mindful of the New Republic's failure to defend them during the war, began building up their Planetary Security Forces to levels that soon caused concern on Coruscant. The Sector Defense Limits of 37 ABY put ceilings on military forces and capabilities, but provoked even more resentment, nowhere more so than on Corellia, a system with a history of prickly independence. Corellian defiance of GA military limits and withholding its reconstruction contributions provoked the Second Galactic Civil War of 40 ABY. After the Galactic Alliance Defense Force continued its efforts to centralize military resources, systems with important shipyards, munitions factories and defense fleets began declaring their independence as well. Led by Corellia, Bothawui and Commenor, they formed a breakaway independent Confederation.
The Battle of Kashyyyk.
With the loss of many of the largest battleships during the Yuuzhan Vong War, neither side made particularly great use of large capital ships. Star Destroyer-sized ships like the Anakin Solo and the new Galactic-class battle carrier predominated on the Alliance side, while the Confederation made use of the somewhat smaller Strident-class Star Defender and the powerful, versatile 850-meter Bothan Assault Cruiser. The Imperial Remnant, meanwhile, began moving away from the traditional design of Star Destroyers with the Turbulent-class "Pocket Star Destroyer", which was smaller and possessed a greater capacity for maneuverability while retaining an impressive armament. A surprising development during the war was a resurgence in Hutt militarism in their deployment of batils, tarradas and chelandions - gunship, frigate and cruiser analogs - from Hutt Space in support of the Confederation. The Hutt warships proved capable in battle, with powerful turbolasers and missiles. They had weaker shields than might be expected of ships of their size, but surprisingly strong hull armor. A technological development during the war was the long-range turbolaser, which could engage enemy craft from a distance at which the enemy could not respond. Such weapons caused heavy losses among the Galactic Alliance Fourth Fleet at the Battle of Balmorra despite the eventual GA victory.
As in the Yuuzhan Vong War, attempts to force a decisive battle by either side were essays in futility. An attempt by the Confederation to invade the Core was halted at Balmorra with heavy losses on both sides. The week-long battle at Kuat ended after the Galactic Alliance Fifth Fleet attacked Kashyyyk to force the Wookiees to commit their fleet to the Alliance. In the ensuing engagement, the Fifth Fleet was almost completely destroyed after it was surrounded by Confederation forces. The Galactic Alliance Second Fleet would later be completely wiped out as well by a deep-space ambush using the Centerpoint superweapon. The Battle of Fondor split the galaxy even further when a third of the Galactic Alliance fleet presented defected under Admiral Cha Niathal out of a refusal to support an orbital bombardment of civilian population centers. A confused civil war ended sometime later with the Battle of Uroro Station at Shedu Maad in the Hapes Cluster.
A Pellaeon-class Star Destroyer fighting with a Scythe-class battle cruiser.
In the aftermath of the war, the Galactic Alliance increased centralized funding of the Defense Force and reduced its reliance on member worlds for defense. In return for increased taxation, restrictions on member worlds' military forces were loosened. For nearly a hundred years, this bargain kept the galaxy largely peaceful. The numbered fleets gave way to larger named fleets assigned to regions of the galaxy, for example, the Galactic Alliance Colonies Fleet. Military philosophy would continue to evolve: in the years leading up to the Sith–Imperial War, the Alliance worked to re-establish Sector Fleets to keep member worlds' warships close to their homeworlds.
Shipbuilding philosophy developed as well. By the start of the Sith–Imperial War in 128 ABY, which saw the resurgence of the Galactic Empire under the Fel Dynasty as the main galactic power at the expense of the Galactic Alliance, both sides had abandoned battleships almost entirely, largely owing to the enormous cost of operating them. The Galactic Alliance's primary warship was now the Scythe-class main battle cruiser, a compact warship only a third of the size of a Star Destroyer that was built for defeating warships in a head-on attack, making repeated attack runs on opponents with an almost-entirely forward-facing armament. Essentially a giant starfighter, its introduction in 92 ABY represented a decisive rejection of fleet carriers and all-purpose battleships in favor of smaller warships focused on specific roles. The Galactic Alliance also retained its focus on the snubfighter with the CF9 Crossfire starfighter. The Fel Empire, meanwhile, continued to prefer the ancient combination of interceptors and bombers, with the heavily-shielded Predator-class fighter and the Neutralizer-class bomber filling its starfighter forces. The Imperial Navy still favoured the Star Destroyer with the Pellaeon-class, though it did not build any larger warships beyond the prototype Imperious-class Star Destroyer. Smaller, lighter warships like the Ardent-class fast frigate were also more common in its fleets than in the Imperial Period.
Rebellion starfighters attack Imperial forces including TIE fighters and Imperial-class Star Destroyers.
The multidimensional battlefield made space warfare operations complex and difficult to master. In addition to the complexities of space combat itself, related operations like logistics and support were equally complex. Strategies in space warfare mirrored those applied on the ground, and included asymmetric, attritional, conventional and psychological strategies.
Asymmetric strategies, for example, the stateless strategy, were often used by belligerents with a numerical disadvantage to their opponents, The various Sith Empires in their endless wars against the Galactic Republic, the Confederacy of Independent Systems, and the Rebel Alliance in its war against the Galactic Empire all used asymmetric strategies. Such strategies relied on decentralization and the sheer vastness of space to allow a smaller belligerent to beat a larger one. A decentralized power without a clearly-defined homeworld or territory would have to be overcome everywhere it existed before it could be defeated. The vastness of space meant that throughout history, even the largest militaries found controlling space impossible. This gave an advantage to the decentralized belligerent: since the larger opponent could not defend everywhere, the smaller power could choose its battles and strike where its opponent was not. This would force the larger power into making the choice between heavily-defending a handful of key "fortress worlds", thus allowing the enemy a free hand elsewhere, or dispersing their forces and so risking the loss of a key planet through defeat in detail. Economic considerations and public pressure tended to force states to adopt the fortress world strategy.
Attritional strategies made use of superior numbers to grind the enemy down, often with large numbers of casualties. Such a strategy was used by the Republic during the Outer Rim Sieges of the Clone Wars: since it possessed territories in its own right, the Confederacy of Independent Systems was vulnerable to being attacked conventionally, and once the Republic's superior industrial base had produced enough warships to both defend their territories and take the offensive, the CIS was slowly ground down to defeat.
Conventional strategies were used by and against belligerents with defined homeworlds and colonies, and involved identifying and attacking significant military objectives to reduce the enemy's territory and military forces. It involved organized military forces seeking to engage each other in formal battles, as opposed to, say, targeting civilian populations. After the Battle of Endor, the Galactic Empire and the New Republic typically fought each other in a conventional fashion.
Psychological strategies involved boosting the morale of one's own forces while degrading that of the enemy's, or that of their civilians, typically through terror tactics. General Grievous saw inducing terror in civilian populations to be the very essence of war, and during the Clone Wars committed atrocities like the release of the Brainrot Plague in the Weemell sector and the orbital bombardment and utter depopulation of Humbarine, which reduced the planet's crust to so much slag. Terror operations could be a response to the stateless strategy, namely the use of reprisal to scare civilians into denying the enemy safe haven. However, this could do more to foment resentment and resistance than it could to combat it. The Galactic Empire's creation of the Death Stars and other superweapons was intended to reverse such a state of affairs by introducing the possibility of a reprisal so terrifying - namely, the destruction of entire planets - that no world would risk aiding the Rebellion. Grand Admiral Thrawn, meanwhile, was a master of a more subtle form of psychological warfare: at the Battle of Ukio in 9 ABY, he made use of cloaked Star Destroyers, slipped below the planet's shields while they were down and coordinated with the rest of his fleet by the Jedi Master Joruus C'baoth, to make it appear that he could shoot through planetary shields, which terrorized the Ukians into surrendering. Later, at Coruscant, he deployed two dozen cloaked asteroids while dry-firing his tractor beams to fake the launch of three hundred more. These asteroids blockaded the planet, and by threatening the possibility of an asteroid impact or a collision with shipping, Thrawn effectively knocked Coruscant out of the war and put it into a permanent state of siege while dedicating hardly any material to the effort.
Astrography affected the conduct of space warfare more than any other factor.
Just as roads and the shape and going of the ground determined where armies marched on the surface of planets, so too did hyperlanes and stellar phenomena like nebulae determined the movements of fleets. This defined what routes they could take, and what star systems they would have to traverse before reaching those of value. Additionally, while there might be a great many hyperspace routes to and from a target, but statistically speaking, only a few of these route could be traversed quickly, and a military force that controlled the fast routes could rapidly redeploy to intercept an adversary using the slow ones. Hyperspace routes also determined the angle at which an attacking fleet might invade a planetary system, and a defender's options for retreat: the Battle of Hoth was a costly battle for the Rebel Alliance because the Hoth system was located on the decaying Ison Corridor, which was difficult to navigate Rimward and had only two exits, making it easy for the Empire to trap the Rebels in-system, and 17 of 30 evacuating transports were lost to the Imperial blockade.
Additionally, control of a point along a hyperspace route enormously influenced military operations in space warfare. If a force controlled a system along a route, then its enemy was separated from the rest of its forces beyond that point. During their advance to the Core Worlds from 4-6 ABY, the New Republic sought to capture several such points. Admiral Firmus Nantz and Lando Calrissian's victory at Abraxas kept Warlord Utoxx Prentioch fixed within his territories around Bomis Koori IV and separated him from Sander Delvardus' Eriadu Authority. Later, Nantz' capture of Moorja isolated Delvardus and Prentioch from support from the Core while Tyr Taskeen's victory at the Battle of Glova prevented Delvardus from linking up with Imperial forces in the Elrood and Minos sectors. Isolated from the rest of the galaxy, the two warlords were dealt with at the Republic's leisure.
Control of junctions of hyperspace routes, like Yag'Dhul or the Mirgoshir hyperspace crossroads, could be enormously decisive. Control of it would allow a force to continue operations along every hyperspace route emanating from it, and so they were often heavily contested. The Galactic Empire withdrew from the Moddell sector to Yag'Dhul in the aftermath of the Battle of Endor to defend against a Rebel drive into the Core from there. After the system was captured by Firmus Nantz in 5 ABY, the entire Southern Core was effectively at his mercy: he was able to capture the strategic bacta-producing world of Thyferra, liberate Cilpar and Mrlsst, and open negotiations with Herglic Space. The most significant hyperspace junction in the galaxy was Brentaal IV, the crossroads of the Perlemian Trade Route and the Hydian Way, which therefore controlled access from the Core Worlds to the northern and eastern quadrants. The system was captured by the Brotherhood of Darkness during the New Sith Wars, and the Sith were only stopped in their march to Coruscant by the Army of Light's desperate counterattack on their supply lines at Ruusan under Lord Hoth. It was captured by the New Republic's Rogue Squadron in 4 ABY six months after Emperor Palpatine's death in a celebrated battle, and its capture effectively separated the Empire from its Outer Rim possessions on the Hydian and the Perlemian, leaving the New Republic free to contemplate the conquest of Coruscant.
The source of a fleet's ships, a shipyard, was very valuable, and made an important target for an opposing force. As they required ships to defend themselves, shipwrights were also very vulnerable and the attacking fleet would often have to destroy heavy opposition before it could damage the docks. The New Republic Second Fleet's campaign in the northern quadrant after 4 ABY was delayed for nearly two years after Imperial forces destroyed the secret shipyards at Hast, destroying or damaging nearly thirty New Republic capital ships and derailing the Second Fleet's planned assault on Warlords Zsinj and Teradoc.
Planets providing strategic material for the war effort were also of paramount importance, because without adequate supplies, after a certain period, any combat starship loses the ability to engage the enemy, either through lack of fuel, lack of munitions, battle damage that cannot be repaired, or the starvation of the crew. Consequently, campaigns could often depend upon cutting the enemy's supply lines, either by attacking its supply ships, or preventing the enemy from reaching their supply ships. If a planet could not be held against an attacking force, then the defender might judge it to be too valuable to be left to the enemy and destroy it. The Imperial Navy codenamed such actions "Base Delta Zero," defined as "the systematic complete destruction of all 'assets' of production, including factories, arable land, mines, fisheries, and all sentient beings and droids", and was achieved through an orbital bombardment that would reduce the upper crust of a planet to slag.
The Guarlara and the Invisible Hand in a broadside battle.
The strategy adopted by a space navy defined what tactics were used in battle. Some tactics were universal: the most basic tactical principle was to maximize the damage one's fleet did to the enemy while minimizing one's own. Other tactics were more suited to certain strategies: space denial, space-sniping and hit-and-hype raiding were generally best suited for a force pursuing an asymmetric strategy, while beambaiting might be adopted by an enemy trying to combat that force.
In general capital ships fought other capital ships, and starfighters fought other starfighters. Exceptions included starfighters equipped with proton torpedoes or other warheads, and capital ships, like the Lancer-class frigate, which were designed to fight starfighters. However, most capital ships were equipped with anti-starfighter cannons to aid their fighter escorts or to serve as the primary defense against fighters in the absence of an escort.
A universal tactic in space battles was maneuvering warships so that they brought more weapons to bear on the enemy than vice-versa, as well as presenting a narrower profile for the enemy to shoot at. Thus, battle formations typically took the form of long lines of ships, hence why capital ships could also be called "ships of the line," to exchange fire with the enemy. A fundamental choice all commanders had to make was whether to engage at long- or close-range. The Galactic Empire typically preferred engagements at range, and the angled, arrowhead design of the Star Destroyer was designed to focus all its weapons forward to accommodate this. This design also made Star Destroyers ideal for launching "Alpha Strikes" - firing all the ship's weapons at a single spot on a target simultaneously to cause maximum damage.
The Star Destroyer's design meant that it was poorly-optimised for close-range battles, however. Close-range engagements typically resulted in broadside battles - two ships flying past each other and firing their side guns into each other's flanks. Mon Calamari Star Cruisers were typically better in broadside battles than their Imperial counterparts, since though they did not have as much total firepower as Star Destroyers, they had a much better all-round firing arc. Ships optimised for broadside battles might attempt to cap the enemy's "T", namely, engage them while they were in a line-ahead formation so that only the lead ship in the enemy formation could respond. They might even rush straight into the enemy's line in the hopes of breaking it, which typically resulted in a chaotic, close-range brawl with ships engaging each other in groups of two or three at most. The late stages of the Battle of Coruscant during the Clone Wars descended into a close-range brawl between Republic and Separatist ships engaging individually in broadside battles after the Open Circle Fleet arrived and trapped the Separatist invasion force in Coruscant's orbit. However, by 4 ABY and the Battle of Endor, brawls were sufficiently rare as to be almost unheard-of in space warfare, and it came as a great surprise to Death Squadron at Endor when Admiral Ackbar closed the Alliance Fleet to within a few hundred meters of them to avoid the superlaser of the Second Death Star. The New Republic Defense Fleet later codified such tactics as the Ackbar Slash.
Long-range and close-range tactics might be combined: the Kenobi Offensive was such a tactic developed by High Jedi General Obi-Wan Kenobi during the Clone Wars, which involved a series of sniping attacks at range to draw a portion of a larger enemy force out of its formation. Once a defending vessel was destroyed, attacking ships could flood through the gap and attack the enemy force from within.
The Imperial Navy Captain Kendal Ozzel identified three principles in Imperial naval tactics, which he recorded in Innovations in Imperial Naval Tactics. The first was Surprise, which involved emerging from hyperspace right on top of the enemy. According to Ozzel, the Imperial navigators were capable of pinpoint calculations, which would eliminate the risk of overshooting the target, and thus leave the enemy unable to counter Imperial offensive moves. The second principle was Pursue, where Imperials were to chase the enemy, largely due to the Star Destroyers' great sublight speed. The third was Overwhelm, which involved the entire Imperial force available being used at once, ensuring that the combined firepower would make up for loss of maneuverability. However, Han Solo implied when reviewing these "innovations" that they were extremely poorly thought out and hardly innovations at all by stating simply, "I can't make fun of this. It's just too easy." This was confirmed when one of Ozzel's innovations, Surprise, resulted in the Rebel-occupied Echo Base on Hoth bunkering down and generating a deflector shield and buying time for an evacuation, thus forcing the Imperials to enter a costly ground campaign, an action that resulted in then-Admiral Ozzel's death at the hands of Darth Vader.
Interdictors could also play a decisive tactical role in space battles. Since their interdiction fields could either prevent the enemy from escaping or pull them out of hyperspace, they could pin an enemy fleet where a commander wanted them. Imperial Immobilizer 418 cruisers prevented a Rebel retreat at Endor, and Grand Admiral Thrawn pioneered revolutionary new uses of interdictors during his final campaign. The Thrawn Pincer was used by him at the Battle of Bilbringi, and called for interdictor cruisers to create a gravity well, which denied the enemy an easy escape. Then, reinforcements could jump through hyperspace into the general area and be pulled out into realspace by the interdiction field behind the enemy with accuracy and surprise which would otherwise be very difficult to achieve. Admiral Ackbar used this same tactic to help defeat the Ciutric Hegemony.
In addition, there was an intelligence element to space warfare, with each side in larger engagements attempting to intercept and decrypt enemy communications as part of a larger effort to predict what the enemy will do next, with the intention of either preventing them from achieving their intentions or minimizing the damage that can be caused by their plans. The Squill Sifters were a group of Galactic Republic spies, slicers and codebreakers active during the Waymancy Storm conflict, and their role in intercepting, deciphering and interpreting Waymancy communications was considered decisive in ending the conflict in a Republic victory.
A Venator-class Star Destroyer executes a Marg Sabl maneuver during the Clone Wars.
Starfighter combat had a huge variety of tactics in its own right, though broadly speaking they could be divided into two groups: those tactics designed to be used against capital ships, and those tactics used to defend capital ships. Historically, the former role had generally been taken by bombers, large, complex and heavy craft built around powerful sensor arrays, large missile payloads, and days-long mission profiles, designed to track down enemy fleets and launch surprise attacks. Naval wisdom held for centuries that this was the only scenario in which torpedo runs could penetrate defensive fighter screens and flak defenses. The latter role was typically taken by interceptors, extremely light, fast and maneuverable starfighters that were minimally armed and were designed to shoot down attacking bombers, or to escort bombers to their targets and defend them from enemy interceptors.
In battle, fleets would typically deploy their interceptor escorts in front of them in a "starfighter screen," where they could engage enemy fighter squadrons before they could close in on the larger vessel. Alternatively they might move aggressively with their starfighters in a tactic like the Marg Sabl closure maneuver. Here, the superstructure of the starfighter-carrying vessel would turn to face the oncoming enemy's vessels, allowing the starfighters to launch without risking attack. The starfighters would then launch attacks over each side of their ships' hulls on to the flanks of the attacking squadrons, who had become pinned against the defending ships. Grand Admiral Thrawn used this tactic against an Elomin commander quite effectively at the Battle of Obroa-skai.
The snubfighter lay between the interceptor and the bomber in terms of armament and speed, and the Alliance Starfighter Corps pioneered their use as shipkillers during the Galactic Civil War, developing a wide variety of tactics that allowed them to destroy much larger capital ships. These included the nova flare, which involved massed barrages of proton torpedoes fired from starfighters and aimed at specific points along the shields of a capital ship. Another such tactic was the Tallon split, a maneuver developed by the Alliance tactician Adar Tallon. The tactic called for two starfighters to fly extremely close together as they approached a capital ship, so close that the larger ship's targeting computer would detect the two fighters as one approaching ship. At very close range, the two fighters would split apart: one fighter would continue on a strafing run of the capital ship, while the second would draw fire away from the first. The attacking fighter would have about five seconds to cause damage on the capital ship before it was clearly identified as a second ship. Even so, those five seconds would allow enough time to cause serious damage to the larger vessel. Garm Bel Iblis' A-wing Slash involved a number of large starfighters masking the approach of smaller starfighters with missile weapons behind them, then moving out in what appeared at first glance to be a flanking attack, wrong-footing the gunners of enemy point defense weapons to allow the force approaching behind the large starfighters to slip through the enemy's defenses, often allowing the smaller fighters' missiles to inflict critical damage to the enemy.
Such tactics suited the Rebel doctrine of space denial, which used hit-and-hype raids against Imperial convoys to deny the Galactic Empire freedom of movement and forced them to commit more forces to convoy defense, thus diluting Imperial naval strength as a whole. A comparable tactic was space-sniping, used by forces defending a star system against a planetary assault. The strategy consisted of hiding starfighter bases in gas giants, within asteroid fields, on planets with large oceans, or on planets with thick cloud cover within or around the planetary system to be defended. Starfighter groups would operate in tandem from these bases, attacking isolated ships during the orbit phase of a planetary invasion.
Starfighter tactics could also extend to smaller capital ships light corvettes or gunships attacking larger ones. Slashing the deck was a tactical maneuver used against enemy capital ships developed by the Dark Lord Kaan at the First Battle of Ruusan during the New Sith Wars. The technique involved any number of smaller ships, usually ranging from snubfighters to corvettes, that would fire all their guns while cutting in along a vector that minimized the amount of guns the enemy capital ship could bring to bear against them. When the enemy capital ship tried to change direction to bring more guns about, the smaller ships would pivot and double back for another pass along a different vector to inflict even more damage. However, the tactic focused heavily on speed and the element of surprise and was almost useless if the enemy could call upon the support of other ships.
Death Squadron in the approach to Hoth.
Space navies were inherently hugely important in making planetary assaults, since they were the only forces that could clear the surrounding space and transport large surface armies. Inevitably, planets also deployed significant defenses, including planetary shields to resist bombardment, and planetary turbolasers, ion cannons, mines, and space defense platforms to fight back against invading fleets.
The Imperial strategist Michael Unther identified four phases of a planetary assault. The approach was the initial advance on the system, and included decisions like at what point to drop the fleet out of hyperspace. A distant approach would allow plenty of time for reconnaissance and might allow the attacking force to approach under stealth, but equally it raised the risk of detection. Alternatively, a close approach might surprise the enemy, but would also leave the fleet exposed with minimal intelligence. During the Battle of Hoth, Admiral Kendal Ozzel brought Death Squadron out of hyperspace too close to the Hoth system in the hope of achieving surprise, but it allowed the Rebels to detect the bursts of Cronau radiation from his ships and rapidly raise a planetary shield around Echo Base. Consequently the Empire was committed to a costly ground assault.
The second phase, orbit, involved the placement of warships around the planet, where they might execute bombardments from an Objective Orbit, or blockade the planet to force it to surrender from a Siege Orbit. The Galactic Empire invested heavily in Dedicated Siege Platforms like the Torpedo Spheres, aimed at blasting down planetary shields with large barrages of proton torpedoes so as to avoid prolonged sieges.
The third phase, invasion, involved the deployment of ground troops to capture the planet. The fleet might be tasked with clearing landing zones, providing precision bombardments in support of the army, or deploying bombers as air support. The fourth phase, control, involved consolidating control of the planet after capitulation. This was typically an army operation, though the navy could be called upon if the aim was to terrify the civilian population into submission, for example, through the use of punitive orbital bombardments.