Map illustrating the geography, demography, and political division of the United States as a result of the Missouri Compromise over the issue of Slavery in 1820–21.
An interactive map of the U.S. in 1854 that allows users to see the economic, demographic, and political makeup of regions and states at the time. Under the Kansas–Nebraska Act of 1854, popular sovereignty allowed the settlers of a federal territory to decide the slavery question without interference from Congress.