The U.S. Coast Survey map calculated the number of slaves in each county in the United States in 1860. Library of Congress. In September of 1861, the U.S. Coast Survey published a large map ...

1860 census map shows distribution of slaves in the Houston area, Southern states. By Heather Leighton, Houston Chronicle March 21, 2018.

This map, made by the U.S. Coast Survey in 1861 using census data from 1860, ... “Map showing the distribution of the slave population of the Suthern states of the United States.

In 1860, a United States census counted nearly four million enslaved people living in the country. The Civil War was fought between abolitionists and the pro-slavery Confederacy, until the ...