He vehemently opposed the seizure of Indian lands by whites, and even killed his own sister by cutting her throat when she talked about surrender[citation needed].
He fought at the Battle of Lake Okeechobee on December 25, 1837, and took control of the Seminole force from their aged warchief Arpeika (also known as "Sam Jones").
After he recovered, Halleck Tustenuggee went on a bloody rampage in north Florida for two years, leading a series of raids and skirmishes.
During the Civil War, Halleck Tustenuggee, along with some of the other Seminole leaders, such as Billy Bowlegs (Sonuk Mikko) and John Chupco, supported the Federal government.
Halleck seems to have been the primary field-commander of the Seminole warriors in three battles – Round Mountain, Chusto-Talasah and Chustenahlah, where they were defeated and forced to flee to Kansas in severe winter weather.