An Indian reservation is an area of land tenure governed by a federally recognized Native American tribal nation under the U.S. Bureau of Indian Affairs, rather than by the government of the state in which it is located. The 326 Indian reservations in the United States are associated with specific Native American nations, often on a one-to-one basis.

Some of the country's 574 federally recognized tribes govern more than one reservation, while some share reservations, and others have no reservation at all. In addition, because of past land allotments, leading to sales to non–Native Americans, some reservations are severely fragmented, with each piece of tribal, individual, and privately held land being a separate enclave. This jumble of private and public real estate creates significant administrative, political and legal difficulties.

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