One of these, whose name was Vitiate, alongside a group of loyal followers and other Sith, fled to the Unknown Regions in order to avoid the Republic's onslaught.
Despite the Republic Military's swift actions to deal with the splinter factions that came to be with the eventual fall of the Pre-Great Hyperspace War Sith Empire, several Sith remained.
With the Sith defeat at the end of the Great Hyperspace War in 5,000 BBY, Supreme Chancellor Pultimo of the Galactic Republic, ordered for the complete annihinaltion of all Imperial Remnants.