
The Arapaho are a tribe of Native Americans historically living on the plains of Colorado and Wyoming. They were close allies of the Cheyenne tribe and loosely aligned with the Lakota and Dakota.

The Bannock tribe were originally Northern Paiute but are more culturally affiliated with the Northern Shoshone. They are in the Great Basin classification of Indigenous People. Their traditional lands include northern Nevada, southeastern Oregon, southern Idaho, and western Wyoming. Today they are enrolled in the federally recognized Shoshone-Bannock Tribes of the Fort Hall Reservation of Idaho, located on the Fort Hall Indian Reservation.

The Blackfoot Confederacy, Niitsitapi or Siksikaitsitapi, is a historic collective name for linguistically related groups that make up the Blackfoot or Blackfeet people: the Siksika ("Blackfoot"), the Kainai or Kainah ("Blood"), and two sections of the Piikani – the Northern Piikani (Aapátohsipikáni) and the Southern Piikani. Broader definitions include groups such as the Tsúùtínà (Sarcee) and A'aninin who spoke quite different languages but allied or joined with the Blackfoot Confederacy.

The Cheyenne are one of the indigenous people of the Great Plains whose language is of the Algonquian language family. The Cheyenne comprise two Native American tribes, the Só'taeo'o or Só'taétaneo'o and the Tsétsêhéstâhese. These tribes merged in the early 19th century. Today, the Cheyenne people are split into two federally recognized Nations: the Southern Cheyenne, who are enrolled in the Cheyenne and Arapaho Tribes in Oklahoma, and the Northern Cheyenne, who are enrolled in the Northern Cheyenne Tribe of the Northern Cheyenne Indian Reservation in Montana.
The Confederated Salish and Kootenai Tribes of the Flathead Reservation are a federally recognized tribe in the U.S. state of Montana. The government includes members of several Bitterroot Salish, Kootenai and Pend d'Oreilles tribes and is centered on the Flathead Indian Reservation.

The Crow, whose autonym is Apsáalooke, also spelled Absaroka, are Native Americans living primarily in southern Montana. Today, the Crow people have a federally recognized tribe, the Crow Tribe of Montana, with an Indian reservation located in the south-central part of the state.

Eastern Shoshone are Shoshone who primarily live in Wyoming and in the northeast corner of the Great Basin where Utah, Idaho and Wyoming meet and are in the Great Basin classification of Indigenous People. They lived in the Rocky Mountains during the 1805 Lewis and Clark Expedition and adopted Plains horse culture in contrast to Western Shoshone that maintained a Great Basin culture.

The Indigenous Peoples of the Great Basin are Native Americans of the northern Great Basin, Snake River Plain, and upper Colorado River basin. The "Great Basin" is a cultural classification of indigenous peoples of the Americas and a cultural region located between the Rocky Mountains and the Sierra Nevada, in what is now Nevada, and parts of Oregon, California, Idaho, Wyoming, and Utah. The Great Basin region at the time of European contact was ~400,000 sq mi (1,000,000 km2). There is very little precipitation in the Great Basin area which affects the lifestyles and cultures of the inhabitants.

The Sioux or Oceti Sakowin are groups of Native American tribes and First Nations peoples in North America. The modern Sioux consist of two major divisions based on language divisions: the Dakota and Lakota; collectively they are known as the Očhéthi Šakówiŋ. The term "Sioux" is an exonym created from a French transcription of the Ojibwe term "Nadouessioux", and can refer to any ethnic group within the Great Sioux Nation or to any of the nation's many language dialects.

The Wind River Indian Reservation is located in the central-western portion of the U.S. state of Wyoming, where Eastern Shoshone and Northern Arapaho Native American tribes currently live. Stretching roughly 60 miles (97 km) east to west and 50 miles (80 km) north to south, the Indian reservation is located in the Wind River Basin and includes portions of the Wind River Range, Owl Creek Mountains, and Absaroka Range.