Antislavery novel written by Harriet Beecher Stowe that showed northerners the violent reality of slavery and drew many people to the abolitionists’ cause. Uncle Tom’s Cabin

Law that made it a crime to help runaway slaves; allowed for the arrest of escaped slaves in areas where slavery was illegal and required their return to slaveholders. Fugitive Slave Act

New country formed by states that seceded from the United States. Confederate States of America

Devotion to the interests of one region instead of to the country as a whole. sectionalism

Incident in which abolitionists killed five slavery supporters. Pottawatomie Massacre

Proposal to outlaw slavery in lands acquired through the Mexican Cession. Wilmot Proviso

Seizure of the federal arsenal at Harpers Ferry, Virginia, by abolitionists. John Brown’s Raid

Political party formed in the 1850s to stop the spread of slavery in the West. Republican Party

Act of formally withdrawing from the Union. secession

Principle that would allow voters in a particular territory to decide whether they wanted to ban or permit slavery. Popular sovereignty

Political party formed in 1848 by antislavery northerners who left the Whig and Democratic Parties because neither addressed the slavery issue. Free-Soil Party

Law that allowed voters in the Kansas and Nebraska territories to choose whether to allow slavery. Kansas-Nebraska Act

Supreme Court ruling that held that African Americans, whether slave or free, were not U.S. citizens under the U.S. Constitution. Dred-Scott decision

Series of events held in Illinois in which candidates for a U.S. Senate seat discussed issues facing the country. Lincoln-Douglas Debates

Political party that recognized no political principles other than the Constitution, the Union, and the enforcement of the laws. Constitutional Union Party