Crow Nation in the context of "Treaty of Fort Laramie (1851)"

Plains Indians or Indigenous peoples of the Great Plains are the Native American tribes and First Nations peoples who have historically lived on the Interior Plains (the Great Plains) of North America. While hunting-farming cultures have lived on the Great Plains for centuries prior to European contact, the region is known for the horse cultures that flourished from the 17th century through the late 19th century. Their historic nomadism and armed resistance to domination by the government and military forces of Canada and the United States have made the Plains Indian culture groups an archetype in literature and art for Native Americans everywhere.

The Plains tribes are usually divided into two broad classifications which overlap to some degree. The first group became a fully nomadic horse culture during the 18th and 19th centuries, following the vast herds of American bison, although some tribes occasionally engaged in agriculture. These include the Arapaho, Assiniboine, Blackfoot, Cheyenne, Comanche, Crow, Gros Ventre, Kiowa, Lakota, Lipan, Plains Apache (or Kiowa Apache), Plains Cree, Plains Ojibwe, Sarsi, Nakoda (Stoney), and Tonkawa. The second group were sedentary and semi-sedentary, and, in addition to hunting bison, they lived in villages, raised crops, and actively traded with other tribes. These include the Arikara, Hidatsa, Iowa, Kaw (or Kansa), Kitsai, Mandan, Missouria, Omaha, Osage, Otoe, Pawnee, Ponca, Quapaw, Wichita, and the Santee Dakota, Yanktonai and Yankton Dakota.

The Cheyenne (/ʃaɪˈæn, ʃaɪˈɛn/ shy-AN, shy-EN) are an Indigenous people of the Great Plains. The Cheyenne comprise two Native American tribes, the Só'taeo'o or Só'taétaneo'o (more commonly spelled as Suhtai or Sutaio) and the Tsétsėhéstȧhese (also spelled Tsitsistas, [t͡sɪt͡shɪstʰɑs]); the 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 Cheyenne language belongs to the Algonquian language family.

Over the past 400 years, the Cheyenne have changed their lifestyles from Great Lakes woodlands to Northern Plains and by the mid-19th century, the US government forced them onto reservations. At the time of their first European contact in the 16th century, the Cheyenne lived in what is now Minnesota. They were close allies of the Arapaho and loosely aligned with the Lakota. By the early 18th century, they were forced west by other tribes across the Missouri River and into North and South Dakota, where they adopted the horse culture. Having settled the Black Hills of South Dakota and the Powder River Country of present-day Montana and Wyoming, they introduced the horse culture to Lakota people around 1730. The main group of Cheyenne, the Tsêhéstáno, was once composed of ten bands that spread across the Great Plains from southern Colorado to the Black Hills in South Dakota. They fought their historic enemies, the Crow and later (1856–79) the United States Army. In the mid-19th century, the bands began to split, with some bands choosing to remain near the Black Hills, while others chose to remain near the Platte Rivers of central Colorado. With the Arapaho, the Cheyenne pushed the Kiowa to the Southern Plains. In turn, they were pushed west by the more numerous Lakota.

The Hidatsa (/hɪˈdɑːtsə/ hih-DOT-sə) are a Siouan people. They are enrolled in the federally recognized Three Affiliated Tribes of the Fort Berthold Reservation in North Dakota. Their language is related to that of the Crow, and they are sometimes considered a parent tribe to the modern Crow in Montana.

A tipi or tepee (/ˈtiːpi/ TEE-pee) is a conical lodge tent that is distinguished from other conical tents by the smoke flaps at the top of the structure, and historically made of animal hides or pelts or, in more recent generations, of canvas stretched on a framework of wooden poles. The loanword came into English usage from the Dakota and Lakota languages.

Historically, the tipi has been used by certain Indigenous peoples of the Plains in the Great Plains and Canadian Prairies of North America, notably the seven tribes of the Sioux, as well as among the Iowa people, the Otoe and Pawnee, and among the Blackfeet, Crow, Assiniboines, Arapaho, and Plains Cree. They are also used west of the Rocky Mountains by Indigenous peoples of the Plateau such as the Yakama and the Cayuse. They are still in use in many of these communities, though now primarily for ceremonial purposes rather than daily living. Modern tipis usually have a canvas covering.