" Language is one way of determining relationships among American Indian nations. The Missouria are of the Siouan-language family, speaking a dialect known as the Chiwere. Other tribes speaking this dialect were the Ho Chunk (Winnebago), the Wahtohtana (Otoe, and the Baxoje (Ioway). William Clark said these tribes spoke the same language and correctly surmised they were "once one great nation. "

― , The People of the River's Mouth: In Search of the Missouria Indians