The main issue of the Missouri Compromise of 1820 was how to deal with the spread of slavery into western territories. The compromise divided the lands of the Louisiana Purchase into two parts. Slavery would be allowed south of latitude 36 degrees 30'. But north of that line, slavery would be forbidden, except in the new state of Missouri. Maine (previously a part of Massachusetts) would enter the union as a free state, balancing out Missouri's pro-slavery senators.

Map by National Geographic Society

Download this file