The Missouri Compromise of 1820 admitted Missouri as a slave state and Maine as a free state, preserving the balance of power in the Senate. However, the compromise also included the provision that slavery would be prohibited in the Louisiana Territory north of the 36°30′ parallel, the southern boundary of Missouri. This provision infuriated many Southerners, who saw it as a violation of their rights. The compromise was ultimately successful in preventing the country from splitting apart, but it also deepened the divisions between the North and the South.
Kansas-Nebraska Act
The Kansas-Nebraska Act of 1854 repealed the Missouri Compromise and allowed the residents of Kansas and Nebraska to vote on whether or not they would become slave states. This led to a wave of violence in Kansas, as pro-slavery and anti-slavery settlers fought for control of the territory. The violence in Kansas played a major role in the outbreak of the American Civil War.
Dred Scott v. Sandford
The Supreme Court decision in Dred Scott v. Sandford (1857) held that African Americans were not citizens of the United States and could not sue in federal court. This decision further inflamed tensions between the North and the South, and it helped to galvanize the abolitionist movement.
John Brown's Raid
John Brown's Raid on Harpers Ferry, Virginia, in 1859 was an attempt to incite a slave rebellion. The raid was unsuccessful, and Brown was captured and executed. However, the raid shocked the nation and further widened the gap between the North and the South.
Election of Abraham Lincoln
The election of Abraham Lincoln as President in 1860 was the final straw for many Southerners. Lincoln was a member of the Republican Party, which was opposed to the expansion of slavery. Lincoln's victory meant that the South would no longer be able to protect its interests in the federal government. As a result, 11 Southern states seceded from the Union and formed the Confederate States of America. The American Civil War began in 1861, and it lasted until 1865. The Union won the war, and slavery was abolished in the United States.