The Untamed were strictly isolationist and ritualistic, having a severe disgust for offworlders. Despite that, they tolerated anyone who respected their ceremonies or bested them in combat, but only temporarily. The Untamed were led by the Beast-Lords.
The Untamed were, according to their leader Akoru, descendants of the ancient Beast Riders of Onderon who were exiled to the wilderness by an outsider, namely the Sith Lord Freedon Nadd. They continued the tradition of inhabiting Onderon's jungles, taming wild beasts such as the pritarrs, and passing along fierce combat abilities.
In 3630 BBY, during the Third Galactic War between the Galactic Republic and Sith Empire, the war arrived on Onderon. Imperial forces under Darth Savik landed secretly on the planet and were able to convince the Untamed to attack the capital Iziz.