Sith Empire (Pre-Republic)

The Sith Empire was established by the Sith of Korriban circa 28,000 BBY after Adas had unified his people with conquest. It lasted until at least 27,700 BBY, when King Adas died following the defeat of the Rakatan invaders.

History
Prior to 28,000 BBY the Sith culture was one of primitive tribal fighting. One Sith, born with a prophesized black pigmented skin, decided to unite his people into an Empire. He took up a gigantic axe and beat the Sith into submission, then set himself up as the first monarch of the Sith people. Having united all of Korriban under one rule, 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 of 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, their capital being relocated from Korriban to the neighboring Ziost.

Peace in the Empire was short-lived, dissolving into civil war due to the death of Adas, with many different leaders claiming the title of Sith'ari. At some point the Empire collapsed in on itself and was long gone by the arrival of the Exiles in 6,900 BBY; and the Sith had once again devolved into a primitive people.