Leading to Civil War

Missouri Compromise (1820) - Compromise was passed for Missouri to be a slave state and Maine as a free state. 

Wilmot Proviso (1846) - Condition to eliminate slavery within land obtained from the Mexican War.

Compromise of 1850  - Agreement in which many compromises were made such as, admitting California as a free state, slave trade ending in Washington, D.C, etc. 

Publication of Harriet Beecher Stowe's Uncle Tom's Cabin (1851-1852) - Novel published by Harriet Beecher Stowe's centered around a slave's life named Uncle Tom.

Kansas-Nebraska Act (1854) - Act that allowed white male settlers to decide whether slavery would be allowed in a certain territory through popular sovereignty.