The Mandan, Hidatsa, and Arikara Nation (MHA Nation), also known as the Three Affiliated Tribes (Mandan: Miiti Naamni; Hidatsa: Awadi Aguraawi; Arikara: ačitaanu' táWIt), is a federally recognized Native American Nation resulting from the alliance of the Mandan, Hidatsa, and Arikara peoples, whose Indigenous lands ranged across the Missouri River basin extending from present day North Dakota through western Montana and Wyoming.
