Ruul, a planetary body situated within the Ruul system of the Core Worlds, is classified as a planet. The Galactic Empire seized control of it, subsequently importing Human prisoners and commencing extensive strip-mining operations.
Prior to 0 ABY, the Empire gained possession of the planet. During this time, the Empire engaged in widespread strip-mining activities. Furthermore, numerous computer complexes were established to house and process substantial quantities of data. The planet also housed Tarkin Detention Facility, an Imperial correctional institution.
In that same year, Grand General Malcor Brashin and Captain Brenn Tantor arrived, discovering that the Alliance to Restore the Republic had taken control of one of the computer complexes. Tantor took back the complex and established a network of remote relay beacons extending to a nearby broadcast antenna. Through this antenna, the complex's data was transmitted to the Inquisitor, revealing crucial intelligence regarding Rebel movements.
Around the period of the Battle of Hoth, an uprising erupted on Ruul. Imperial Intelligence dispatched Major Dellis Tantor to suppress it. The rebellion persisted even after Brenn Tantor returned to the planet as a Rebel, several months after his brother's assignment, possibly because Tantor's mission was a ruse for his capture by the Empire, in which he had lost faith. Tantor liberated Beri Tulon from Tarkin Detention Facility and carried out an intelligence-gathering operation targeting the computer complex located at Sounder Flats.
Brenn Tantor referenced the Imperial assault on Ruul in the video game Star Wars Galaxies. However, the game erroneously conflated the planet Ruul with the moon Ruul of Sriluur.