The agreements made in order to admit California into the Union as a state in which slavery was illegal.

a Supreme Court decision in 1857 that held that African Americans could never be citizens of the United States and that the Missouri Compromise was unconstitutional

A person who flees or tries to escape (for example, from slavery) 

an act passed in 1854 that created the Kansas and Nebraska territories and abolished the Missouri Compromise by allowing settlers to determine whether slavery would be allowed in the new territories 

a series of political debates between Abraham Lincoln and Stephen Douglas, who were candidates in the Illinois race for U.S. senator, in which slavery was the main issue 

the United States as one nation united under a single government. During the Civil War, “the Union” came to mean the government and armies of the North. 

an agreement made by Congress in 1820 under which Missouri was admitted to the Union as a state in which slavery was legal and Maine was admitted as a state in which slavery was illega

a proposal made in 1846 to prohibit slavery in the territory added to the United States as a result of the Mexican-American War