Free-Soil Party: Founded in Buffalo, the main goal was to keep slavery out of the western territories.
Popular Sovereignty: The idea that the people have the right to create their government.
Wilmot Proviso: A failed law meant to ban slavery in areas won during the Mexican-American War.
Missouri Compromise: Henry Clay's proposal meant to keep the number of slave states and free states equal.
Allowed California to enter the Union as a Free State.