This semi-nomadic group lived in tepees on the plains of South Dakota for several hundred years. Primarily an agricultural society, corn was their main crop and was so important it was often referred to as "Mother Corn." In 1823, the Arikara, frustrated with traders encroaching upon their lands, attacked a group of white travelers, resulting in the short-lived Arikara War. In the late 1830's, the tribe was almost destroyed by small pox. In the 1870's they were forced by the Sioux out of the Black Hills and migrated into North Dakota where they began to work closer with the Hidatsa and Mandan tribes who inhabited the area. Today, they are still associated with the Hidatsa and Mandan, known collectively as the Three Affiliated Tribes. The Arikara live primarily on the Fort Berthold reservation in North Dakota.