Telosians constituted the population residing on the Outer Rim planet known as Telos IV.
During 3958 BBY, Admiral Saul Karath committed an act of treachery against the Republic by initiating a surface bombardment of Telos IV. This attack resulted in the death of most Telosians present on the planet's surface, including Carth Onasi's wife.
Following the conclusion of the Jedi Civil War, the Telosian Restoration Project was established, with its primary goal being the revitalization of Telos's ruined surface and its return to a habitable state. During this period, the Telosians primarily resided on the colossal Citadel Station orbiting the planet.
Eventually, the planet's surface became habitable once more, leading to the development of urban centers, notably including Thani, which served as the capital city.