Susan Schulten, University of Denver history professor, has an interesting piece in the New York Times (online) on the last map prepared of the U.S. enslaved population (1860). Here is a small version of the map:

This map was prepared by the Coastal Survey from 1860 census data, and the source is “Map Courtesy of Geography and Map Division, Library of Congress.” You can see Schulten’s very useful interactive and larger-annotated map here. This should be useful for classes dealing with the background and demography of slavery just at the beginning of the Civil War.

Schulten makes some interesting points about the map:

The map reaffirmed the belief of many in the Union that secession was driven not by a notion of “state rights,” but by the defense of a labor system. . . . the map measured each state’s slave population, and contemporaries would have immediately noticed that this corresponded closely to the order of secession. South Carolina, which led the rebellion, was one of two states which enslaved a majority of its population. . . . the map [also] illustrated the degree to which entire regions—like eastern Tennessee and western Virginia—were virtually devoid of slavery, and thus potential sources of resistance to secession.

President Abraham Lincoln loved the map (as did many in the Union’s public) and apparently used it in his own planning and thinking about the Civil War. It likely supported his

belief that secession was animated by a minority and could be reversed if Southern Unionists were given sufficient time and support. . . . The map gave a clear picture of what the Union was up against, and allowed Northerners to follow the progress of the war and the liberation of slave populations.

She points out that this map enabled Lincoln to focus on a key feature of the secessionist states—their slavery system of labor. For the views of those enslaved in this system of labor see the first part of this book.