Considered the birthplace of the Mantellian Separatist Movement, Avilatan was a contested island during the Cold War. Several key locations on Avilatan during the Separatist War included the Republic's base of operations, Fort Garnik, and the Separatists' base of operations, Mount Avilatan, which contained the Separatist stronghold.
The Avilatan Badlands was one of many contested battle zones on the island. Several villages, such as Drelliad, Oradam, and Talloran, were also on the island. Nearby, the island of Mannett Point was a key base for Separatist forces.
Avilatan was home to many indigenous species. Mantellian flutterplumes could be found in small packs throughout the island. Flutterplumes often fed on soldiers killed during battle. Mantellian Savrips could be also be found in Avilatan, although they mostly resided on an island nearby.