The Sith Council was comprised of ten Sith Lords within the Sith Empire who acted as advisors to the current Dark Lord of the Sith. This group of Sith convened in a great citadel situated on the planet Ziost. The Council was responsible for the administration of the Empire's affairs. Each Lord who was a member of the Council held dominion over at least twelve worlds.
In 6900 BBY, after the Exiles had established their capital on Ziost, Ajunta Pall gathered the high-ranking and ambitious individuals who had followed him and formed the Sith Council. The Council's meetings were held within a great citadel located on Ziost.
Under the rule of Marka Ragnos, five of the ten Sith Lords who served on the Council were Naga Sadow, Ludo Kressh, Simus, Dor Gal-ram, and Horak-mul. Following Ragnos's death, Naga Sadow and Ludo Kressh, two Lords on the council, engaged in a power struggle for the position of Dark Lord of the Sith. This dispute caused a division within the council, with some lords supporting Kressh and the remainder backing Sadow.
Ultimately, Sadow managed to persuade the council to appoint him as Dark Lord by falsely claiming that the Galactic Republic was conducting raids within the Empire. After Kressh uncovered the deception, he and two other lords attacked Sadow's fortress, but they were decisively defeated, allowing Sadow to solidify his claim to the title.
The Sith Lord Vitiate summoned the remaining Council members, along with nearly 8,000 other Sith, to his homeworld of Nathema, where he dominated their minds and coerced them into participating in the Ritual of Nathema—an action that resulted in the death of everyone on Nathema except for Vitiate.
In a scene from Tales of the Jedi – The Golden Age of the Sith 3, the faces of eight members are displayed (excluding Naga Sadow and the already deceased Simus). Aside from Sadow, only one other individual on the council appears to possess Dark Jedi lineage, indicated by the absence of prominent eyebrow ridges and a flattened nose.
The Essential Chronology refers to the group as both "a tribunal of Sith Lords" and the "Sith council."