There are two options for mapping NHGIS data. The first is to download our GIS (geographic information system) files and load them into a GIS or statistical package. The second option is to create maps using Social Explorer, an online mapping application.
Download GIS Files
NHGIS provides boundary and point data in the shapefile format for historical census tracts, counties, states, metropolitan statistical areas, and several other geographic levels. In order to use these data, a user must have access to a GIS application or statistical software package, such as R, that will read shapefiles.
To browse available GIS files and select any for download, use the NHGIS Data Finder. After you have specified some set of filters, click on the "GIS BOUNDARY FILES" tab under Select Data. You can browse and select data without an account, but you must register (at no cost) and log in to complete your data request.
Create Maps Online
Social Explorer is an online research tool that lets users create maps using historical boundary data from NHGIS.