The Sith Empire is a fictional galactic government in the Star Wars universe. It was established by a group of Dark Jedi who were exiled from the Galactic Republic and discovered a remote planet called Korriban. There, they encountered the Sith species, and over time, the Dark Jedi intermarried with the Sith, creating a new Sith society.
The Sith Empire’s first major conflict with the Galactic Republic occurred in the Great Hyperspace War, which took place about 5,000 years before the events of the original Star Wars trilogy. The Sith Empire was defeated, but it continued to exist in a weakened state.
The Sith Empire made a resurgence about 3,500 years later, during the time of the Old Republic. Led by a powerful Sith Lord named Vitiate, the Sith Empire launched a massive invasion of the Republic, known as the Great Galactic War. The Sith were initially successful, but the war eventually ended in a stalemate.
The Sith Empire was re-established once again about 300 years later, during the time of the Jedi Knight Revan. Revan, who had turned to the dark side of the Force, became the Dark Lord of the Sith and led the Sith Empire in a war against the Republic. However, Revan ultimately turned back to the light side and helped defeat the Sith Empire.
There have been several other iterations of the Sith Empire in the Star Wars universe, including during the time of the Galactic Empire, as depicted in the Star Wars: The Old Republic video game, and in the Star Wars: The Rise of Skywalker film.