The Endar Spire, a Hammerhead-class cruiser, served the Galactic Republic Navy during the Jedi Civil War. It was assigned to Jedi Knight Bastila Shan in 3956 BBY, with a crew that included the experienced commander Carth Onasi, Ensign Trask Ulgo, Revan, and various Republic soldiers. This vessel was part of a larger Jedi battle fleet, deployed to counter the invading forces of Dark Lord of the Sith Darth Malak's Sith Empire.
While in orbit above the planet Taris, the Endar Spire came under attack from Malak's Sith forces. A contingent of the Dark Lord's army, commanded by Darth Bandon, boarded the cruiser with the objective of capturing Shan alive. These Sith troopers and Dark Jedi killed the majority of the Endar Spire's crew, while Sith warships and starfighters maintained the ship's structural integrity as the boarding party attempted to seize Shan. Revan, Ulgo, and Onasi fought the Sith and progressed towards the ship's bridge in order to find Shan, who had already evacuated. Soon after, Revan and Onasi escaped in an escape pod, with Ulgo sacrificing himself to ensure their survival. Upon realizing Shan was no longer on board, the Sith fleet opened fire on the Endar Spire, obliterating it completely.
The Endar Spire was a Hammerhead-class cruiser utilized by the navy of the Galactic Republic. Rendili Hyperworks was the manufacturer of the vessel. The ship, measuring 315 meters in length, was equipped with four double light turbolaser batteries, two medium turbolaser batteries, two point-defense laser cannon batteries, and one tractor beam battery. Its deck layout was identical to that of another Hammerhead-class cruiser, the Harbinger. The engines, bow, and dorsal section were painted red, while the primary hull color was white.
The Endar Spire's complement included Republic soldiers, who were responsible for defending the ship from enemy boarding actions. Many of these soldiers, along with the ship's Commander, the Jedi Knight Bastila Shan, one Jedi Master, and at least two other Jedi, were present when the Sith Empire attacked the Endar Spire in 3956 BBY. At the time of the attack, other crew members included Revan, who had lost all memories of his past as a Jedi Knight and Dark Lord of the Sith, as well as Republic Captain Carth Onasi and Ensign Trask Ulgo. The ship also carried at least one droid, which was programmable for combat roles. The corridors of the Endar Spire were white, with maroon stripes running across them and gray flooring. Illumination was provided by illuminated panels. The ship's corridors included a series of blast doors that could be magnetically sealed to defend against enemy boarding parties. Crew quarters were designed to accommodate two individuals, but due to rotating shifts, roommates rarely encountered each other. The Endar Spire's bridge, located in the bow, housed the ship's navigation computer. Computer terminals lined the bridge's outer walls, each with a chair. A wide viewport wrapped around the front, port, and starboard sides of the bridge, providing a three-directional view of space. Escape pods were located on the command deck, accessible via a door on the bridge. The vessel carried at least four escape pods.
During the Jedi Civil War, the Endar Spire was tasked with transporting the Jedi Knight Bastila Shan. The Jedi Council advised that the amnesiac former Dark Lord of the Sith Revan be assigned to the crew, allowing Shan to monitor him closely, lest they trigger the return of Revan's memories of the Star Forge, the superweapon employed by the Sith Empire. The Endar Spire was attached to a larger Jedi battle fleet, with the mission of defeating the Sith Empire's invasion fleet at the planet of Taris.
Shan's battle meditation skills were crucial to the Republic's war effort. Darth Malak, the leader of the Sith Empire, believed that capturing Shan alive would allow him to convert her to the dark side. The Sith learned of Shan's presence on the Endar Spire and planned to ambush the warship, unaware that Revan was also on board. The Sith flagship, the Leviathan, was positioned above the ecumenopolis to intercept the ship as it exited hyperspace and initiate a boarding action. The Endar Spire, carrying its crew, was unaware of the impending ambush. When the Endar Spire was pulled out of hyperspace, a Sith boarding party, led by Malak's apprentice Darth Bandon, consisting of Sith troopers and at least one Dark Jedi, boarded the vessel.
Upon the Sith boarding, Republic soldiers immediately engaged them. The noise of the battle, along with Ulgo, woke Revan. Revan, having had his memory erased, believed he was a regular Republic crewman who had been drafted onto the Endar Spire prior to the mission. Meanwhile, Onasi ordered all available Republic personnel to report to the bridge. As a Jedi fought a Dark Jedi that Bandon had brought aboard, Ulgo and Revan hurried to obey Onasi's command. The Sith, wanting to capture Shan alive, avoided using firepower that would destroy the Endar Spire outright. Shan, realizing that the Sith's primary objective was to capture her, headed towards the starboard escape pods in an attempt to deny the Sith their prize.

When Revan and Ulgo arrived at the bridge, they found the last of the Republic soldiers being slaughtered by a Sith squad. They killed the squad, but were confronted by Darth Bandon. Ulgo, to allow Revan to reach the escape pods and Onasi, who had just ordered the ship abandoned, engaged the Sith Apprentice, sacrificing himself for Revan's sake. Revan reached the pods, entered the last capsule with Onasi, and escaped the doomed ship. By this time, Shan, along with at least three Republic soldiers, had already evacuated. Realizing their target was no longer on board, Bandon returned to the Sith fleet, and the Sith opened fire on the Endar Spire, destroying it moments after Onasi's and Revan's capsule had launched.

Although severely damaged, the ship managed to record the subsequent Bombardment of Taris. The Endar Spire eventually crashed on the planet, likely after the bombardment. Surprisingly, the ship remained mostly intact. Generations of survivors visited the wreckage of the Endar Spire, though not all with peaceful intentions. By the time of the Great Galactic War, pirates had established a presence in and around the remains of the Endar Spire.
In an attempt to recover recordings of the Sith Bombardment, the Republic infiltrated the wreckage of the ship. The Republic ultimately recovered the recordings, which were used to prevent a disaster similar to Taris.
The Endar Spire made its debut in the game Star Wars: Knights of the Old Republic, developed by BioWare. The player is introduced to the gameplay and timeline of the game aboard the Spire in the opening sequence. The areas, composed of two distinct sets of maps and multiple rooms, include the command deck, escape pod bay, and crew quarters. Unlike most environments in Star Wars: Knights of the Old Republic, the player has limited ability to alter their interactions with the surroundings aboard the Endar Spire.
Gameplay choices on the Endar Spire are limited to methods of eliminating enemies and dialogue options with characters. The player's actions have no impact on the fate of the Endar Spire or its crew. Its second appearance is in the game Star Wars: The Old Republic. Players are tasked with retrieving data logs still stored within the ship, which has been overrun by scavengers.
Although only one ship is depicted, Chronicles of the Old Republic Part XI indicates that the Endar Spire was part of a much larger Jedi battle fleet deployed to stop Darth Malak's invasion force at Taris; however, this fleet has not been mentioned since.
The cutscene depicting the Endar Spire's destruction in Knights of the Old Republic shows the ship being completely vaporized, while The Old Republic features a mostly intact crash site on the surface of Taris, seemingly contradicting the earlier game's depiction of the ship's fate.