At the time of the great migration of emigrants through Wyoming to the Pacific coast and Utah, Indians were the largest group of residents in Wyoming. Many of these tribes such as Utes and Blackfeet, were semi-permanent and nomadic, traveling in and out of Wyoming as warrior-hunting societies. The roaming buffalo supplied the Indians with all their subsistence, and the introduction of the horse provided the mobility to hunt the buffalo in great numbers.
The Shoshoni were located in the western part of Wyoming, generally in the Green River valley. The Crows were living in the Big Horn and Powder River Basins in northern Wyoming and southern Montana. The Cheyenne, Arapaho, and Sioux claimed the southeast part of Wyoming, an area heavily traveled during the emigrant migration.
The coming of the emigrants in great numbers was accepted peacefully by the Crow and Shoshoni, but the Sioux, with the help of the Cheyenne and Arapaho, resisted fiercely. From 1853 until 1877, the Sioux and their allies fought this intrusion in numerous battles until final defeat forced them to accept the invasion and reservation life. In Wyoming, the Wind River Indian Reservation is home for the Arapaho and Shoshoni.