The resources below include data and resources from US government agencies, non-profit, and other academic institutions based on the following themes: historical; political/demographic/administrative, natural sciences; social/health; transportation; general, other. This is not a comprehensive list; however, these sites have been seen as useful points of reference.
Historical
General (Multiple Thematic Areas)
Non-Government Sources (Multiple Thematic Areas)
Political/Demographic/Administrative
Non-Profit Organizations
U.S. Geological Survey
U.S. Department of Agriculture
U.S Department of Education
National Institutes of Health (NIH)
National Oceanic and Atmospheric Administration (NOAA)
National Park Service
Federal Emergency Management Agency
U.S. Department of Housing and Urban Development
Bureau of Indian Affairs
U.S. Fish and Wildlife Service
Bureau of Ocean Energy Management
National Weather Service
Defense
U.S. Department of Transportation
U.S. Environmental Protection Agency
U.S. Energy Information Administration