I’ve had this idea kicking around in my head for a while, but I finally sat down and did the thing.

US Population Density 1790-1860

Data source: Minnesota Population Center. National Historical Geographic Information System: Version 2.0. Minneapolis, MN: University of Minnesota 2011.

The website of the NHGIS: NHGIS.org, and NHGIS are great people hosting great data and if you’re into history or GIS you should know about them because they are great.

A few caveats about this map: the pre-1810 data doesn’t include Native Americans, and because I don’t have hard data, implies that areas to the West of the then-United States were unpeopled before White people did the Manifest Destiny thing and stole all the land. After 1810, I am unsure whether the data includes Native Americans, but I doubt it. And this wasn’t true, but as this map is focused on the United States and is supposed to reflect how the country looked to people in the American Government at the time, I didn’t look for data on Native American and Mexican populations during this time period. If anyone knows a good source for that data, let me know.

Now, the second map:

Slaves as Percentage of Population, 1790-1860

Data source: Minnesota Population Center. National Historical Geographic Information System: Version 2.0. Minneapolis, MN: University of Minnesota 2011.

There was going to have a companion map showing the percentage of populations that were free people of color. but the data for some time periods conflated free people of color and all people. That map is still in progress, once I figure out the right NHGIS data to incorporate.

Very interestingly, in 1790 the Northeast had a sizable number of slaves, and as time passed and the Northern states abolished slavery, their slave populations dropped to 0. However, the Southern slave population went up and up and up, until many counties, in the Carolinas and along the lower Mississippi River, had between 75% and 90% of their populations in chains. This, to my mind, lends an interesting support to the idea that Southern slave society was terrified of slave rebellions. When you’re outnumbered 10-to-one by people you’ve exploited, raped, and abused, it’s easy to be afraid of them.

I’ll probably make more of these as I compile data.