Iroquois, Native American tribes of the Iroquoian linguistic family, members of the Iroquois League. This political union of the Mohawk, Oneida, Onondaga, Cayuga, and Seneca tribes was founded in the 16th century by the Onondaga chief Hiawatha and Dekanawida, formerly a Huron. The Tuscarora joined in 1722. Hunters and farmers, the Iroquois tribes lived in stockaded villages of longhouses. Families were matrilineal, and belonged to an intertribal clan system. During the French and Indian Wars the Iroquois supported the British, but the league split over the Revolutionary War.