Reservations in the Great Plains are territorial units retained by Native American tribes, either as remnants of their ancestral lands, or as designated areas assigned after removal—from both within and outside the region—following the cession of homelands to the United States. They are places where tribal and federal jurisdictions prevail, to the general exclusion of state jurisdiction, though the legal boundaries here are constantly shifting with new decisions in the courts. Great Plains reservations are generally poor places, mineral resources and revenues from gaming notwithstanding. But they are also treasured homelands where ancestors are buried, sacred sites revered, and cultures preserved; for their Native American residents, they are the surviving geographic connection between past and present.

The first reservations in the Plains, other than the relatively large areas set aside for relocated Indians such as the Delawares in the 1820s and 1830s, were created after the Kansas- Nebraska Act of 1854 opened up the area to European American settlement. Because of this incursion, the idea of a separate, extraterritorial "Indian Country" in the Plains, which had prevailed since 1830, became impractical. Instead, Plains Indians would be restricted to small areas recognized in treaties, laws, or executive orders as belonging to them. The remaining homelands would then be available for resettlement by European Americans. On the reservations, Native Americans would be placed under great pressure to assimilate—to take out individual farms, or allotments, to learn English, and to convert to Christianity. When this occurred, theoretically, the Native Americans would simply merge into the larger society, and any additional reservation lands over and above their allotments would also pass to European Americans. In this sense, then, and despite the recognition in treaties of Indian rights to the lands, reservations were seen by the United States in the mid– nineteenth century as only a temporary expedient until Native Americans assimilated. But Native Americans in the Plains, and elsewhere in the United States, did not disappear through assimilation, or through war and disease. Thus, reservations have remained a significant component of the region's identity.

By 1860 the Indians of eastern Nebraska (e.g., the Pawnees) and eastern Kansas (e.g., the Kaws) had sold their remaining homelands to the United States, retaining only small reservations. In the following decades reservations were created successively west, north, and south (in Indian Territory) from the initial area of European American advance, as tribes, under varying degrees of coercion, were forced to cede their lands. In 1868, for example, at the Treaty of Fort Laramie, the Crows surrendered 38 million acres of their hunting grounds in what is now Montana and Wyoming and agreed to a reservation in south-central Montana. In 1874 and 1888 the Blackfeet relinquished about 27 million acres of land in Montana and took out a reservation where the Plains meets the Rocky Mountains at the fortyninth parallel. By the latter date, all Plains tribes had been restricted to reservations.

Despite the "recognized" or "reserved" title under which the Plains tribes hold their reservations, their size and the Indians' sovereignty on them have been eroded almost from the beginning. Those early reservations in Kansas and Nebraska were quickly surrounded and coveted by settlers. By 1881 the Kaws, Pawnees, Poncas, and Otoe-Missourias had all been removed to Indian Territory and their reservations thrown open to resettlement. Even when original reservations were retained, as in the cases of the Crows and Blackfeet, the Indians were forced by settlers' demands, and by their own poverty, to sell portions to the United States in return for subsistence. The Crow Indian Reservation, for example, was significantly reduced by cessions in 1882 and 1892, and the size of the Blackfeet Reservation was almost halved in 1895.

Even greater losses from Plains reservations occurred after passage of the General Allotment (Dawes) Act of 1887. At various times thereafter, Indians were allocated individual allotments (generally 160 acres), and the portions of reservations remaining after that allocation were declared "surplus lands" that were opened to European American settlement. In 1904, on the Devils Lake Sioux Reservation in North Dakota, for example, 135,824 acres were allotted to 1,193 Indians, leaving 92,144 acres of surplus lands to be sold to settlers at $1.25 an acre. Subsequently, following a government trust period, many of the allotments were also sold to settlers. As a consequence, non-Indians now own 75 percent of the Devils Lake Sioux Reservation. This is a characteristic pattern on many Plains reservations, which are a "checkerboard" of Indian and non-Indian lands, greatly complicating jurisdiction and compromising tribal sovereignty.

On a map of Indian reservations in the United States, the Northern Great Plains stands out. There are still many Native Americans in Oklahoma, of course, as the successor to Indian Territory, but with the exception of the Osage Reservation, all the reservations were dissolved in the years leading up to statehood. (Many Indian groups in Oklahoma own tribal lands, and some refer to their lands as reservations, but for census purposes they are designated as Tribal Jurisdiction Statistical Areas.) There are no reservations in the Texas Plains, where, after statehood in 1846, the state controlled land disbursement and made no room for the Indigenous inhabitants. There are relatively few (seven) remaining reservations in Kansas and Nebraska, the result of Indian removals in the nineteenth century. But north of the Nebraska–South Dakota border, reservations abound (there are seventeen of them), and most are large. The 1,771,082-acre Pine Ridge Reservation, for example, with its tribally enrolled population of 17,775 in 1995, is one of the largest reservations in the country. It is also one of the poorest places in the country, with 60 percent of families living below the poverty level in 1990. Even on the 2,235,095- acre Crow Indian Reservation in Montana, with its rich resources of coal, oil, and gas, per capita income in 1995 was only $4,243 and unemployment stood at 44 percent.

Despite the promises of the United States, spelled out in treaties and agreements, the status of Plains reservations remains insecure, especially because of state intervention. In an important case in 1981, Montana v. United States, the U.S. Supreme Court ruled that the Crow tribe does not have the right to regulate nonmember hunting and fishing on reservation lands that are not owned by, or held in trust for, the tribe. The only exceptions are if the activity threatens tribal integrity or if consensual agreements have been made. Similarly, in federal district court in North Dakota in 1993, the Devils Lake Sioux were held to have the right to contract for electrical services only on lands owned by, or held in trust for, the tribe, which meant only about one-quarter of the area of the reservation. These decisions indicate that the geographic extent of Indian sovereignty is being moved from the exterior boundaries of the reservation to those areas within the reservation held in trust by the tribe or by members of the tribe.

Yet, in other ways, the Indian presence on Plains reservations is resurgent. In a region where rural populations are rapidly thinning, Indian reservations stand out as areas of significant population growth. Birthrates are higher than average, and death rates, though still high, have fallen. Moreover, Indians are returning to reservations to fill jobs created by gaming and other economic development. New revenues mean that reservation lands once alienated can be reclaimed. Far from disappearing, Native Americans and their reservation homelands are reasserting themselves on the landscape of the Great Plains.

See also CITIES AND TOWNS: Reservation Towns / LAW: Montana v. United States.