In 1830, a series of debates took place in the United States Senate over the issue of national sovereignty versus state sovereignty. Daniel Webster, Senator from Massachusetts, argued for national sovereignty and preserving the union. Webster stated: “Liberty and Union, now and forever, one and inseparable.” Robert Hayne, Senator from South Carolina, argued that the states were sovereign and had given limited power to the national government.

Abraham Lincoln and Stephen Douglas competed against each other in 1858 in an election for an Illinois seat in the U.S. Senate. The two men debated each other seven times, and the debates often focused on the issue of slavery. These debates brought Lincoln and the issue of slavery further into the national spotlight. Douglas argued for popular sovereignty (voting by the people) to decide the issue of slavery in the western territories, while Lincoln argued to stop the spread of slavery in the West. Although Lincoln lost to Douglas, the debates brought him national attention and helped him win the presidency in 1860.

John Brown was a radical abolitionist who resorted to violence in his attempts to defeat slavery. In 1859, he led a raid on a federal arsenal (a collection of weapons and military equipment) at Harper’s Ferry, Virginia. His hope was to arm slaves and lead an uprising, but he was captured, tried for treason, and hanged for his crime.