Listing of all Historical U.S. County Boundary Maps by State by Year

View historical U.S. county boundaries for every state for every year since state or territory formation. From 1629 through the year 2000, these maps show each state’s counties as they existed in that historical year, all overlaid on a present-day Google Map so that you can put historical county lines in present-day context.

These 10,584 different maps depict county lines from each state for each year in the 1600s, 1700s, 1800s, 1900s to the year 2000. These historical county maps are built using the complete dataset of the authoritative Newberry Library’s Atlas of Historical County Boundaries project.