Crow Warrior Sitting
Pressured by the Ojibwe and Cree peoples (the Iron Confederacy), who had earlier and better access to guns through the fur trade, the Crow had migrated to this area from the Ohio Eastern Woodland area of present-day Ohio, settling south of Lake Winnipeg. From there, they were pushed to the west by the Cheyenne. Both the Crow and the Cheyenne were pushed farther west by the Lakota (Sioux), who took over the territory west of the Missouri River, reaching past the Black Hills of South Dakota to the Big Horn Mountains of Wyoming and Montana. The Cheyenne eventually became allies of the Lakota, as they sought to expel European Americans from the area. The Crow remained bitter enemies of both the Sioux and Cheyenne.
From about 1740, the Plains tribes rapidly adopted the horse, which allowed them to move out on to the Plains and hunt buffalo more effectively. However, the severe winters in the North kept their herds smaller than those of Plains tribes in the South. The Crow, Hidatsa, Eastern Shoshone and Northern Shoshone soon became noted as horse breeders and dealers and developed relatively large horse herds. At the time, other eastern and northern tribes were also moving on to the Plains, in search of game for the fur trade, bison, and more horses. The Crow were subject to raids and horse thefts by horse-poor tribes, including the powerful Blackfoot Confederacy, Gros Ventre, Assiniboine, Pawnee, and Ute.
Their greatest enemies became the tribes of the Blackfoot Confederacy and the Lakota-Cheyenne-Arapaho alliance.