During the era of the Reconquest of the Rim, these were the boundaries defining Imperial Space.
The expanse under the control of the Galactic Empire, subsequently known as the Imperial Sector and then Bastion space, was designated as Imperial Space. This domain was later governed by the Imperial Remnant and the Fel Empire. Spanning nearly the entire known galaxy during the Imperial Era, it stretched from the Core Worlds all the way to the Outer Rim. The designation "Imperial Space" gained prominence particularly after the New Republic ascended as the predominant governing force in the galaxy.
Following the fall of Coruscant and the Core Worlds in 6 ABY, the Empire was stripped of its status as the galactic government. In this period, the majority of the remaining Imperial territory was divided amongst various warlords.
The actual Imperial territory encompassed certain sectors squeezed between Zsinj's Empire and the Pentastar Alignment within the Outer Rim Territories. It also included a region south of the Pentastar Alignment, extending from the Inner Rim to the Outer Rim, along with several star systems scattered across the galaxy and detached from these main areas.
After the death of Warlord Zsinj, Admiral Teren Rogriss successfully reclaimed a small portion of Zsinj's Empire along the Hydian Way, but he was soon pushed back.
During his relatively brief but impactful campaign, Grand Admiral Thrawn managed to seize a substantial number of sectors and star systems, thereby enlarging his empire across all galactic regions, from the Outer Rim Territories to the Core Worlds. At the time of his death, he held control over more than a third of the galaxy, a territory comparable in size to that of the New Republic. Not until the emergence of the Fel Empire would the Empire attain such vastness again.
Having returned from the clutches of death, the resurrected Emperor Palpatine consolidated the various warlords and Imperial factions, initiating Operation Shadow Hand with the intent of reasserting his dominion over the galaxy. Employing his formidable superweapons, he reclaimed a significant amount of territory, stretching from the Outer Rim to the Core Worlds. During this period, the Borderland Regions acted as a buffer zone, delineating the boundary between the New Republic and the Empire.
The name of this era corresponds to the color of the armor worn by the primary Imperial leader of the time, Carnor Jax. Following his ascension, the New Republic launched a swift assault, resulting in the loss of much of the territory previously regained by the reborn Palpatine by the former Emperor's Royal Guard and his successors. They managed to retain only a narrow strip of territory extending from the Outer Rim to the Colonies. Furthermore, the Pentastar Alignment and various other warlords reasserted their independence following Palpatine's demise. After the Crimson Empire fell, the New Republic announced that the true Empire was no more, with only warring warlords in the Deep Core, Moffs focused on fortifying their heavily defended worlds, and the Pentastar Alignment, which had no intention of fighting the New Republic, remaining.
The designation "Pellaeon's Empire" was applied to Imperial Space starting in 12 ABY, subsequent to the Imperial Reunification and the establishment of the Imperial Remnant. Following the Conference at Tsoss Beacon, Admiral Pellaeon relocated the unified Deep Core forces to the Outer Rim Territories, extending as far as Wild Space and bordered to the east by the Hydian Way. This newly formed domain incorporated territory previously held by the Crimson Empire, the Ciutric Hegemony, the Pentastar Alignment, Moff fortress worlds, and semi-independent sectors like Admiral Gaen Drommel's Oplovis Sector and Moff Getelles' Antemeridian Sector.
As a reaction to Imperial aggression in 17 ABY, the New Republic initiated a major campaign, deploying the full strength of the New Republic Fleet. The Imperial forces suffered significant losses, and Imperial Space was subsequently diminished to encompass only eight sectors. This situation compelled Pellaeon to seek peace negotiations with the New Republic in 19 ABY.
Following the conclusion of the Yuuzhan Vong War, the Imperial Remnant reclaimed the territory it had lost to the Yuuzhan Vong, in addition to securing a significant number of sectors that had been aligned with the New Republic prior to the war. Capitalizing on the weakened state of the Galactic Alliance, the Imperial Remnant retained control of these sectors. During this period, the Imperial Remnant was sometimes referred to as the Galactic Empire.
- The formerly known eight "backwater" sectors: Braxant sector Carrion sector Half of Clacis sector Dynali sector Obtrexta sector Perinn sector Half of Prefsbelt sector Velcar sector
- Territories liberated and annexed at the end of the Yuuzhan Vong War : Albarrio sector Atrivis sector Cademimu sector Cassander sector The remaining half of Clacis sector Dantus sector Fath sector Halthor sector Lahara sector Myto sector Oplovis sector The remaining half of Prefsbelt sector Raioballo sector Relgim sector Eleven sectors located in the Mid Rim, including Ariarch sector, Barsa sector, Belshar sector, Chaama sector, Churnis sector (excluding the Gilatter system), half of Glythe sector, portions of Droma and Irishi sectors, Jalor sector, Londori sector, and half of Pacor sector. Two sectors situated in the Expansion Region: Carvandir sector and Deadalis sector.
- Territories offered by Jacen Solo during the Second Galactic Civil War : Bilbringi system Borleias