American Indian reservation An American Indian entity with boundaries established by treaty, statute, and/or executive or court order. Federal and individual State governments have established reservations as territory over which American Indians have governmental jurisdiction. These entities are designated as colonies, communities, pueblos, rancherias, reservations, and reserves. The Federally recognized reservations, their names, and their boundaries are identified for the Census Bureau by the Bureau of Indian Affairs (BIA), an agency in the U.S. Department of the Interior; State governments identify the names and boundaries of State reservations.
American Indian subreservation area An administrative subdivision of an American Indian reservation, known as an area, chapter, community, district, or segment. These entities are internal units of self-government or administration that serve social, cultural, and/or economic purposes for the American Indians on the reservation. Subreservation areas may lie wholly or partially within an American Indian reservation; a few are located entirely outside any reservation (off-reservation). Tribal governments identified and delineated subreservation areas for the Census Bureau for the 1980 decennial census, the only census in which the Census Bureau has tabulated data for these areas.
American Indian trust land Land held in trust by the Federal government for either a tribe (tribal trust land) or an individual member of that tribe (individual trust land). Such land always is associated with a specific Federally recognized reservation or tribe, but may be located on or off the reservation. The Census Bureau recognizes and tabulates data separately only for off-reservation trust lands. The BIA identifies and provides maps of these areas for use by the Census Bureau.
Analysis unit (AU) A small geographic area consisting of one or more contiguous census blocks, created by the Census Bureau to evaluate their land area and population density and to determine if they should be included in a UA area or extended city. See also extended city, urbanized area.
