Missouri Compromise: Primary Documents in American History
Enacted in 1820 to maintain the balance of power in Congress, the Missouri Compromise admitted Missouri as a slave state and Maine as a free state. This guide compiles Library of Congress digital materials, external websites, and a print bibliography.
Author: Ken Drexler,Reference Specialist, Researcher and Reference Services Division
Created: March 7, 2019
Last Updated: March 7, 2019
In an effort to preserve the balance of power in Congress between slave and free states, the Missouri Compromise was passed in 1820 admitting Missouri as a slave state and Maine as a free state. Furthermore, with the exception of Missouri, this law prohibited slavery in the Louisiana Territory north of the 36° 30´ latitude line. In 1854, the Missouri Compromise was repealed by the Kansas-Nebraska Act. Three years later the Missouri Compromise was declared unconstitutional by the Supreme Court in the Dred Scott decision, which ruled that Congress did not have the authority to prohibit slavery in the territories.