The Union was destroyed in 23,900 BBY following the end of the Tionese War, fought by the Union against the Galactic Republic and the Hutts. At that time, the former worlds of the Union (with the exception of Desevro) joined the Republic as a member sector with Tion as the capital.
- The New Essential Guide to Characters
- Geonosis and the Outer Rim Worlds
- The New Essential Chronology
- The Complete Star Wars Encyclopedia
- The Essential Guide to Warfare