National Historical Geographic Information System

The National Historical Geographic Information System (NHGIS) is a historical GIS project to create and freely disseminate a database incorporating all available aggregate census information for the United States between 1790 and 2000. The project has created one of the largest collections in the world of statistical census information, much of which was not previously available to the research community because of legacy data formats and differences between metadata formats. In addition, NHGIS has created cartographic boundary files compatible with every census, and over 50 million lines of metadata describing the collection. The statistical and geographic data are disseminated free of charge through a sophisticated online data access system.

NHGIS was launched in 2007 and is maintained by the Minnesota Population Center at the University of Minnesota and is funded by the National Science Foundation and the National Institutes of Health.