HidatsaMandanArikara

The HidatsaMandanArikara, commonly known as the Three Affiliated Tribes, refers to the three closely related Indigenous peoples—the Hidatsa, Mandan, and Arikara—who historically inhabited the Missouri River valley in central North Dakota. The three tribes share linguistic roots within the Missouri River Siouan language group and formed a long-standing alliance that included village life, farming, trade, and mutual defense. Before modern relocation, Mandan villages along the upper Missouri were notable for earth-lodge towns, while Hidatsa and Arikara communities also practiced substantial farming and seasonal movement.

The Mandan, Hidatsa, and Arikara languages are distinct but related. Traditionally they lived in semi-sedentary communities and shared cultural practices such as matrilineal kinship and clan systems, skilled agriculture (maize, beans, squash), hunting, fishing, and extensive trade networks with neighboring Indigenous groups and European traders after contact in the 18th and 19th centuries.

In the 19th century, European colonization, disease, and U.S. government policies led to the loss of traditional lands and relocation to new reservations. The Three Affiliated Tribes are now federally recognized and governed under a unified tribal government based at New Town, North Dakota, within the Fort Berthold Reservation. They continue cultural preservation and language revitalization efforts, while engaging in contemporary governance and economic development as a single political entity.