The Sphere of Ancient Knowledge, alternatively referred to as the Pyramid of Ancient Knowledge or the Ministry of Ancient Knowledge, functioned as one of the twelve Spheres of Influence within the structure of the Sith Empire. A Dark Councilor presided over this Sphere, which held the responsibility of safeguarding and augmenting the body of Sith knowledge.
Charged with the protection and study of ancient Sith lore, the Pyramid of Ancient Knowledge served as a center of power for the Sith Empire. Similar to other power structures within the Empire, it comprised numerous sub-factions of Sith Lords, each striving to enhance their own power and status within the Sith hierarchy. Regardless of the specific faction they belonged to or controlled, all members of the pyramid ultimately reported to the Dark Councilor who led it.
Between the years 3642 BBY and 3640 BBY, the pyramid experienced three changes in leadership. Following the death of Darth Arctis under mysterious circumstances, Darth Thanaton assumed control. However, Thanaton's reign was short-lived, as he was defeated in a Kaggath by his rival, Lord Kallig. Kallig triumphed before the Dark Council, and Darth Mortis, the leader of the Sphere of Laws and Justice, ended Thanaton's life. Upon their return to Dromund Kaas, the allies and servants of both Kallig and Thanaton swore fealty to the new Dark Lord of the Sith and Dark Councilor.
Later, on Rishi, Moff Pyron, a lieutenant of Darth Nox, informed Nox about ongoing military operations. He suggested that Nox seek out Lord Veijel, who claimed to have discovered a method for achieving immortality. Despite Talos Drellik's reservations, Nox provided Veijel with the resources necessary to pursue their objective of eternal life.
After the war against Zakuul, Empress Darth Acina restructured the Spheres of Influence into five new council seats. The Sphere of Ancient Knowledge was merged with the Spheres of Mysteries and Sith Philosophy to form the Sphere of Sith Doctrine. Darth Anathel subsequently became the leader of these three combined spheres.
Depending on the choices made by the player after becoming a member of the Dark Council, Darth Nox could either purge the sphere of Thanaton's supporters, mandate an increase in efforts to uncover lost Sith rituals and artifacts, or simply declare that the Sphere would focus on fighting the Republic.
If the player chose to spare Harkun and Achelon, they would be present and offer their respects to the Sphere's new leader. If Achelon was killed, Kirnon would assume his position.
Should Darth Nox kill Darth Anathel and rejoin the Sith Empire, they would once again lead the Sphere of Ancient Knowledge, which would then be known as Sith Doctrine.