The Dominus sector constituted a sector situated within the Outer Rim Territories. Specifically, it was located within the region known as the Slice, spanning quadrants T-7, U-7, and U-8. A minimum of seven star systems were contained within its boundaries.
This sector, called Dominus, was found in the galactic area referred to as the Slice. This region, described as the "cradle of galactic civilization," lies between the Perlemian Trade Route and the Corellian Trade Spine. It was situated in the Outer Rim Territories and encompassed quadrants T-7, U-7, and U-8.
Within the Dominus sector were the following planets: Baros, Dominus III, Dornea, Solanus, Solay, and Trailia. Moreover, it incorporated a nebula known as the Dark Nebula.
One hyperspace route at least, specifically Prously's Rim Run, traversed the sector, providing a link between Baros and Dornea and the adjacent Calamari sector.
The space that the Dominus sector occupies was first explored at some point between the Great Hyperspace War occurring in 5000 BBY and the Kanz Disorders around 3000 BBY. By the time of 0 ABY, it had become an established sector. During this period, Luke Skywalker, Princess Leia, along with Wedge Antilles, conducted reconnaissance of the sector to identify a suitable location for establishing a base. An Imperial force attacked them, compelling them to retreat.
During the early years of the Galactic Empire's rule—a government spanning the galaxy, intended to fix the issues of the previous Galactic Republic—the Empirical, a concealed space station that functioned as the central point for the Phase Zero dark trooper project, was located in the Dominus system. Captain Juno Eclipse, who was the pilot of the starship Rogue Shadow, underwent torture onboard the station and was branded as a traitor to the Empire.
In 9 ABY, forces under Grand Admiral Thrawn attacked Baros, as part of the major operation of his campaign.
During the Yuuzhan Vong War, local Yuuzhan Vong forces launched probes into the Dominus sector. Dornean Navy forces, commanded by General Etahn A'baht, successfully fought off these attacks.
By 137 ABY, the Dominus sector fell within the territory controlled by Darth Krayt's Galactic Empire.
The Brubbs represented a bipedal reptilian species originating from Baros, a world within the Baros system. Through adaptation, their ancestors developed thick skin and transparent membranes over their eyes to protect themselves from the arid planet's sandstorms. The constant howling winds also resulted in an almost complete loss of hearing. Due to Baros' strong gravity, Brubbs possessed greater strength than their average height of 1.5–1.7 meters would suggest. Additionally, Brubbs could alter their skin color, with shades ranging from yellow to greenish–gray.
Brubbs were social creatures, residing in communal groups referred to as habas, which typically consisted of extended families who raised their children and jointly managed a specialized business. "University" habas included the most intelligent and capable individuals from other habas, and their technology was on par with galactic standards, especially in the domains of solar and wind power. Obo Rin, an Imperial sentientologist and xenobiologist, noted in his project Catalog of Intelligent Life in the Galaxy that one of the university habas established contact with the Empire by transmitting radio signals.
The Dorneans, with their purple skin, hailed from Dornea and were a proud species known for their extensive martial history. Their naval heritage traced back to a time when they were confined to their homeworld's oceans, predating their mastery of space travel. The Dorneans were adept at defensive tactics, particularly the male members, who were responsible for childcare.
During the rule of Emperor Palpatine, the Dorneans repulsed the Imperial Navy using only a small fleet of their own. The Dorneans later allied with the New Republic.
The Trailians, humanoid beings who were Force-sensitive, evolved on Trailia and, by the time of the New Republic (a government that was reformed from the Alliance of Free Planets and had previously been a rebel organization), they possessed a peaceful, low-tech society. Cronal, a servant of Emperor Palpatine aligned with the dark side, discovered Trailia following 5 ABY and set up a laboratory within its jungles. He captured native Trailians, genetically engineered them, and subjected them to dark side experiments, transforming them into a race of warriors intended for use against the New Republic. He sent some of these warriors to raid other planets, which led the remaining Trailians to offer a reward for an investigation, thereby attracting a group of offworlders to Trailia.
A Force-sensitive member of the team detected the dark side presence of Cronal's laboratory and guided the group there. In an engagement, they overcame the mutated Trailians and other creatures guarding the fortress. However, Cronal managed to escape the battle, along with some warriors who continued to devastate offworld cities before being located and eliminated by the same team.