Thustra was a planet located within the Thustra system, Sumitra sector of the galaxy's Expansion Region. It was also the homeworld of a Near-Human race known as the Sephi. Until the advent of the Clone Wars, Thustra was a member world of the Galactic Republic, and was thus represented in the Galactic Senate by a senator. By 21 BBY, approximately nine months into the civil war, the Sephi betrayed the Republic and joined Thustra with the rebellion of the Confederacy of Independent Systems.