Slavery and the Admission of States in the U.S.

One interesting fact about the formation and admission of states in the U.S. is the “unwritten” policy to admit states generally to preserve the balance between free and slave states. For example, the first thirteen states were split seven free states and six slave states. The fourteenth state KY was a slave state. When Ohio (a free state) was admitted in 1803, it was followed in 1812 by Louisiana (a slave state). Thereafter, states were admitted two at a time---- one slave and one free state--- in order to preserve the delicate balance between the two systems. This practice continued uninterrupted until the Civil War.

Map showing the balance of power between free and slave states (cir. 1830)