The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior responsible for administering federal lands. Headquartered in Washington, D.C., and with oversight over , it governs one eighth of the country's landmass.
President Harry S. Truman created the BLM in 1946 by combining two existing agencies: the General Land Office and the Grazing Service. The agency manages the federal government's nearly of subsurface mineral estate located beneath federal, state and private lands severed from their surface rights by the Homestead Act of 1862. Most BLM public lands are located in these 12 western states: Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming.
The mission of the BLM is "to sustain the health, diversity, and productivity of the public lands for the use and enjoyment of present and future generations." Originally BLM holdings were described as "land nobody wanted" because homesteaders had passed them by. All the same, ranchers hold nearly 18,000 permits and leases for livestock grazing on of BLM public lands. The agency manages 221 wilderness areas, 29 national monuments and some 636 other protected areas as part of the National Conservation Lands (formerly known as the National Landscape Conservation System), totaling about . In addition the National Conservation Lands include nearly 2,400 miles of Wild and Scenic Rivers, and nearly 6,000 miles of National Scenic and Historic Trails. There are more than 63,000 oil and gas wells on BLM public lands. Total energy leases generated approximately $5.4 billion in 2013, an amount divided among the Treasury, the states, and Native American groups.
The BLM's roots go back to the Land Ordinance of 1785 and the Northwest Ordinance of 1787. These laws provided for the survey and settlement of the lands that the original Thirteen Colonies ceded to the federal government after the American Revolution.