It is the home of several federally recognized bands of Assiniboine, Lakota, and Dakota peoples of Native Americans.

With a total land area of 2,094,000 acres (8,470 km2; 3,272 sq mi),[5] it is the ninth-largest Indian reservation in the United States.

The Hunkpapa and assorted Teton peoples gained some supplies from contact with the Sioux at what was then known as the Fort Peck Agency.

The federal government increased its military forces in the area in an effort to induce Sitting Bull to surrender.

Without supplies and barely tolerated by the First Nations peoples in the area of present-day southern Saskatchewan, who were dealing with limited resources, Sitting Bull returned to the United States.

In 1884, Wolf Point was suffering from extreme poverty and starvation, so the Indian Rights Association convinced Congress to make a special appropriation for them.

From 1885 to Montana Statehood in 1889, the tribes participated in agreements with the US government to re-drawing the Fort Peck reservation boundaries in exchange for federal subsidies.

[8] In 1887, Congress passed the Dawes Act, which provided the general legislation for dividing the allegedly tribally-owned Indian reservations into parcels of land under individual titles.

In 1913, approximately 1,348,408 acres (5,456.81 km2; 2,106.888 sq mi) of unallotted or tribal unreserved lands were available for settlement by the non-Indian homesteaders.

[9] Educational history on the Reservation includes a government boarding school program that was begun in 1877 and finally discontinued in the 1920s.

The Fort Peck Reservation is served by five public school districts, which are responsible for elementary and secondary education.

[10] For some years, the Fort Peck Indian Reservation was the location of a branch campus of the NAES College.

Fort Peck Reservation is home to two separate Indian nations, each composed of numerous bands and divisions.

The official governing body of the Fort Peck Tribes is the Tribal Executive Board, composed of twelve voting members, plus a chairman, vice-chairman, secretary-accountant, and sergeant-at-arms.

In March 2012, 63 American bison from Yellowstone National Park were transferred to the Fort Peck Indian Reservation prairie, to be released to a 2,100-acre (8.5 km2; 3.3 sq mi) game preserve 25 miles (40 km) north of Poplar.

The Assiniboine and Gros Ventre tribes at the Fort Belknap Indian Reservation will also receive a portion of this herd.

[16] In November 2014, an additional 136 American Bison from Yellowstone National Park were added to the Fort Peck Herd.