The Sith Empire, named the Kingdom of the Sith in rumors abroad, was a theocratic monarchy established by the Sith of Korriban circa 28,000 BBY when Adas unified the many scattered Sith tribes on Korriban and established himself as the sole ruler and lord of Korriban. Three hundred years later, King Adas died following the defeat of the Rakatan invaders. After the king's death, the Empire was torn apart in the ensuing power struggle as many warlords claimed kingship for themselves. Dathka Graush temporarily unified his people for his fifty year reign, but was assassinated by his own council.
The Empire was reunified for a short time at some point before 6900 BBY, with the rise of King Hakagram Graush—who was deemed a proper successor. Soon after that however, Dark Jedi Exiles arrived and seized power on Korriban. They then took the name Sith for their own and became a sect of Force-sensitives who utilized the dark side of the Force.
Prior to 28,000 BBY the Sith culture was one of primitive tribal fighting. One Sith, born with prophesied black pigmented skin, sought to unite the people of Korriban into an Empire, and succeeded by setting himself up as the first monarch of the Sith people. Having united all of Korriban under one rule, Sith King Adas was given the title of Sith'ari, or Lord of the Sith.
King Adas' rule lasted 300 years until in 27,700 BBY, when, while fighting off the Rakata invaders, he lost his life. His death was not in vain however, as he and his people had forced the Rakata off Korriban. Taking what remained of their enemies' spacecraft, the previously primitive Sith—now instantly propelled into a space age and armed with mastery of the dark side of the Force, both acquired from the Rakata—went on to conquer other nearby worlds, in what would later come to be known as Sith Space. Foremost among these worlds were Ziost, Malachor V, Tund, Jaguada, Thule, and Arorua, with their capital being relocated from Korriban to the neighboring Ziost.
Peace in the Empire was short-lived, dissolving into a civil war due to the power vacuum caused by the death of Adas, with many different leaders claiming the title of Sith'ari. During this chaos, Dathka Graush rose to power through a brutal campaign in which he overtook two-thirds of Korriban. Graush was eventually assassinated by his own followers, deemed too insane and bloodthirsty to rule by a species famous for its brutality. However, relics of his rule remained to be studied by Sorzus Syn and the Exiles when they arrived on Korriban about fifty years after Graush died in c. 6950 BBY.
At some point before the year 6900 BBY, two-dozen millennia after Adas' death, a suitable successor to Adas seemed to come at last: Hakagram Graush was made King of the Sith. However, Graush's reign was short-lived. Following the Battle of Corbos, a group of fallen Jedi Exiles arrived on Korriban thanks to Sorzus Syn's pursuit of the fabled Kingdom of the Sith, and the Dark Jedi soon seized power by assassinating the king and impressing the Sith people with their mastery of the Force.
- Tales of the Jedi – The Golden Age of the Sith 0 (In flashback(s))
- Tales of the Jedi – The Golden Age of the Sith 2 (In flashback(s))
- Tales of the Jedi 5 (First appearance) (In flashback(s))
- Star Wars: The Old Republic (Codex entry)
- Darth Bane: Dynasty of Evil (Indirect mention only)
- Darth Bane: Dynasty of Evil audiobook (Indirect mention only)
- Darth Plagueis (Indirect mention only)
- Darth Plagueis audiobook (Indirect mention only)
- Knights of the Old Republic Campaign Guide
- Evil Never Dies: The Sith Dynasties
- The Essential Atlas
- Book of Sith: Secrets from the Dark Side
- Star Wars: The Ultimate Visual Guide: Updated and Expanded
- Star Wars: Build the Millennium Falcon 82 (Guide to the Galaxy: Moraband) (as Kingdom of the Sith)