Chickasaw a tribe of North American Indians belonging to the Muskhogean language group. They are related to the Choctaws, Creeks, and Seminoles in language and culture. The Chickasaw were one of the most warlike tribes of the Gulf of Mexico area, and nearly wiped out De Soto's expedition in 1540. Their population at that time, centered in northern Mississippi, is estimated at 3,000 to 5,000.

They were valuable allies of the English in the wars with the French. The Chickasaw were forced over a period of time to give up portions of their lands to the United States government; they ceded their final holdings in treaties of 1832 and 1834. In 1837 the Chickasaw were removed to Indian Territory (now Oklahoma), where they formed one of the Five Civilized Tribes.