Humanities › History & Culture Top 9 Events That Led to the Civil War Share Flipboard Email Print History & Culture Military History Civil War Battles & Wars Key Figures Arms & Weapons Naval Battles & Warships Aerial Battles & Aircraft French Revolution Vietnam War World War I World War II American History African American History African History Ancient History and Culture Asian History European History Genealogy Inventions Latin American History Medieval & Renaissance History The 20th Century Women's History View More By Martin Kelly History Expert M.A., History, University of Florida B.A., History, University of Florida Martin Kelly, M.A., is a history teacher and curriculum developer. He is the author of "The Everything American Presidents Book" and "Colonial Life: Government." our editorial process Martin Kelly Updated August 07, 2019 While the American Civil War (1861–1865) was devastating for the United States in terms of human loss of life, it was also the event that caused the American states to finally become united. Slavery—the "cruel, dirty, costly and inexcusable anachronism, which nearly ruined the world's greatest experiment in democracy," as American historian W.E.B. DuBois wrote—is often given as a one-word answer for the cause of the Civil War. But although it was the key catalyst, as historian Edward L. Ayers has said, "History does not fit on a bumper sticker." A variety of events prompted the war, not just the underlying issues of slavery and states' rights. From the end of the Mexican War to the election of Abraham Lincoln, the war’s roots were numerous and diverse. 01 of 09 1848: The Mexican War Ends Treaty of Guadalupe Hidalgo. CORBIS / Corbis via Getty Images With the end of the Mexican War in 1848 and the Treaty of Guadalupe Hidalgo, America was ceded western territories. This posed a problem. As these new territories would be admitted as states, would they be free or slave states? To deal with this, Congress passed the Compromise of 1850, which basically made California free and allowed the people in Utah and New Mexico to choose for themselves. This ability of a state to decide whether it would allow slavery was called popular sovereignty. 02 of 09 1850: The Fugitive Slave Act Passes Corbis via Getty Images / Getty Images The Fugitive Slave Act was passed as part of the Compromise of 1850. This act forced any federal official who did not arrest a runaway slave to pay a fine. This was the most controversial part of the Compromise of 1850 and caused many abolitionists to increase their efforts against slavery. This act also prompted more activity along the Underground Railroad as fleeing slaves made their way to Canada. 03 of 09 1852: 'Uncle Tom's Cabin' Is Published Historical Picture Archive/CORBIS/Corbis via Getty Images "Uncle Tom's Cabin or Life Among the Lowly" was written in 1852 by Harriet Beecher Stowe. Stowe was an abolitionist who wrote this book to show the evils of slavery. The book became a best-seller and had a huge impact on the way that Northerners viewed slavery. It helped further the cause of abolition, and even Abraham Lincoln recognized that this book's publication was one of the events that led to the outbreak of the Civil War. 04 of 09 1856: 'Bleeding Kansas' Riots Shock Northerners MPI / Getty Images In 1854, the Kansas-Nebraska Act was passed, allowing the Kansas and Nebraska territories to decide for themselves using popular sovereignty whether they wanted to be free or slave. By 1856, Kansas had become a hotbed of violence as pro- and anti-slavery forces fought over the state's future to the point where it was nicknamed "Bleeding Kansas." The widely reported violent events were a small taste of the violence to come with the Civil War. 05 of 09 1856: Charles Sumner Attacked by Preston Brooks on the U.S. Senate Floor Bettman / Getty Images One of the most publicized events in Bleeding Kansas was when, on May 21, 1856, the Missouri pro-slavery activists known as the "Border Ruffians" sacked Lawrence, Kansas, which was known to be a staunch free-state area. One day later, violence occurred on the floor of the U.S. Senate. Pro-slavery Congressman Preston Brooks attacked the abolitionist Senator Charles Sumner with a cane after Sumner had given a speech condemning the pro-slavery forces for the violence occurring in Kansas. 06 of 09 1857: Dred Scott Loses His Case to Be Free Hulton Archive / Getty Images In 1857, Dred Scott lost his case that argued that he should be free because he had been held as a slave while living in a free state. The Supreme Court ruled that his petition could not be seen because he did not hold any property. But it went further, stating that even though he had been taken by his "owner" into a free state, he was still a slave because slaves were to be considered the property of their owners. This decision furthered the cause of abolitionists as they increased their efforts to fight against slavery. 07 of 09 1858: Kansas Voters Reject the Lecompton Constitution Bettman / Getty Images When the Kansas-Nebraska Act passed, Kansas was allowed to determine whether it would enter the Union as free or slave. Numerous constitutions were advanced by the territory to make this decision. In 1857, the Lecompton Constitution was created, allowing for Kansas to be a slave state. Pro-slavery forces supported by President James Buchanan attempted to push the Constitution through the U.S. Congress for acceptance. However, there was enough opposition that in 1858 it was sent back to Kansas for a vote. Even though it delayed statehood, Kansas voters rejected the Constitution and became a free state. 08 of 09 October 16, 1859: John Brown Raids Harper's Ferry Hulton Archives / Getty Images John Brown was a radical abolitionist who had been involved in anti-slavery violence in Kansas. On October 16, 1859, he led a group of 17, including five black members, to raid the arsenal located in Harper's Ferry, Virginia (now West Virginia). His goal was to start a slave uprising using the captured weapons. However, after capturing several buildings, Brown and his men were surrounded and eventually killed or captured by troops led by Colonel Robert E. Lee. Brown was tried and hanged for treason. This event added more fuel to the growing abolitionist movement that helped lead to open warfare in 1861. 09 of 09 November 6, 1860: Abraham Lincoln Is Elected President Iconic in life, President Abraham Lincoln proved just as interesting in death. Pgiam/E+/Getty Images With the election of Republican candidate Abraham Lincoln on November 6, 1860, South Carolina followed by six other states seceded from the Union. Even though his views about slavery were considered moderate during the nomination and presidential campaign, South Carolina had warned it would secede if he won. Lincoln agreed with the majority of the Republican Party that the South was becoming too powerful and made it part of the party platform that slavery would not be extended to any new territories or states added to the Union. Sources and Further Reading Ayers, Edward L. "What Caused the Civil War?" North & South: The Official Magazine of the Civil War Society 8.5 (2005): 512–18.Bender, Thomas, ed. "Rethinking American History in a Global Age." Berkeley CA: University of California Press, 2002. DuBois, W.E.B. "Black Reconstruction: An Essay Toward a History of the Part Which Black Folk Played in the Attempt to Reconstruct Democracy in America, 1800–1860." New York: Russell and Russell, 1935. Goen, C. C. "Broken Churches, Broken Nation: Denominational Schisms and the Coming of the American Civil War." Macon GA: Mercer University Press, 1988.Kornblith, Gary J. "Rethinking the Coming of the Civil War: A Counterfactual Exercise." Journal of American History 90.1 (2003): 76–105.McDaniel, W. Caleb, and Bethany L. Johnson. "New Approaches to Internationalizing the History of the Civil War Era: An Introduction." The Journal of the Civil War Era 2.2 (2012): 145–50.Woodworth, Steven E. and Robert Higham, eds. "The American Civil War: A Handbook of Literature and Research." Westport CT: Greenwood Press, 1996.