- "Thousands of years before the Republic conceived of the notion, a species known as the Rakata turned Belsavis into a prison planet. From what little scientists have learned by studying ancient writings and from the decaying memory banks of Rakata warden droids, Belsavis was built to hold monsters, warlords and so-called “lords of the infinite”–anything the primeval and incredibly powerful Rakata feared. The Belsavis prison administration calls the Rakata section of Belsavis “the Tomb.” Here, prisoners are held in eternal stasis, frozen in place and denied movement and thought by ancient technologies. Not all the inmates are ancient, however–many were given by the Republic to the warden droids for safekeeping, when no other cell could hold them. Through the use of droids, remote-controlled probes and rare exploratory teams, the Republic has set up a series of monitoring and communication stations throughout the Tomb. Despite this, only a tiny portion of the Tomb has been explored; this is the domain of the ancients."
- ―In-game Codex (Locations)
The Tomb was a Rakatan prison located on Belsavis that was converted into a Republic prison. It housed many of the galaxy's most dangerous beings. It later served as home to many of the Republic's enemies, including the Sith, their allies, and their creations.
Fifty years before the events of The Old Republic, the Tomb was discovered by Republic scientists navigating Belsavis' sparse jungles. After the prison was found, exploration attempts were impeded by the prison's complex structure, the violent droids guarding it, and the prisoners themselves. Once it realised that the prison's systems could fail at any moment, the Republic established a new prison, officially named "The Tomb" by the Strategic Information Service. When the Great War began, the Tomb began to fill with enemies of the Republic that, reagardless of the reason, could not be executed. Eventually, Imperial Intelligence learned of the prison's existence and sent strike teams to rescue the loyal Imperials held captive within. Following the strike teams' arrival, the Tomb became a labyrinthine battleground as the strike teams fought to rescue their comrades from the Republic guards and other prisoners that escaped in the ensuing chaos.