Between 1860 and 1861, 11 slaveholding states in the southern United States seceded from the Union and established their own republican government. Their secession was motivated by a desire to preserve slavery and the lifestyle of the agrarian South that depended on it. When President Abraham Lincoln ordered U.S. troops to defend Fort Sumter from Confederate takeover, the nation plunged into a devastating Civil War that lasted four years.

The Election of Abraham Lincoln

Although prominent voices in the South had been advocating secession over perceived hostility toward slavery for decades, tensions reached their pinnacle during the 1860 presidential election. The Democratic party split three ways, and this divided opposition allowed Republican Abraham Lincoln to win the election. Lincoln garnered less than 40 percent of the popular vote, without winning a single slaveholding state. Until Lincoln's election, Southern political leaders had dominated the executive and legislative branches of the federal government. Lincoln was publicly hostile to slavery and advocated preventing its expansion into the western territories. To many in the South, his election threatened their livelihood.

South Carolina Leads the Way

On December 24, 1860, South Carolina became the first state to officially secede from the Union, doing so even before President Lincoln took the oath of office. The official declaration alleged that Northern states and the federal government had violated their Constitutional duties and encroached on the rights of the Southern states. This wasn't the first time South Carolina had turned to the idea of secession. As early as 1776, South Carolina threatened to secede over a Continental Congress proposal to tax states proportionately based on population numbers that included slaves. Again in 1830, the state threatened to secede over high federal tariffs. In 1860, however, the state followed through with its threats, and other states followed suit. In the months to follow, six other states in the deep South joined the newly formed Confederate States of America: Alabama, Florida, Georgia, Louisiana, Mississippi and Texas.

The Institution of Slavery

In 1860, nearly 75 percent of U.S. exports came from the South, and these agricultural products relied heavily on slavery. When Mississippi seceded, its declaration stated clearly that the separation was "thoroughly identified with the institution of slavery -- the greatest material interest in the world." The right to own slaves was recognized in the Constitution, yet states in the North had passed laws allowing the freedom of escaped slaves. The Confederate states pointed to the explicit guarantee of the Constitution that slaves who escaped to a non-slave state would be returned to their owners. The states that passed laws to the contrary were violating the Constitution, but the federal government was not protecting the interests of the South by allowing them to persist.

The Right to Secede

The social contract theory of government that had provided a theoretical grounds for the American Revolution was also used to justify secession. From the point of view of the Confederate states, the Constitution was a contract to which all states agreed. If the federal government failed to meet its obligations under this contract, the states were under no obligation to honor it. Just as the colonists had rebelled against oppressive British rule, the Confederacy rebelled against the oppression and despotism of the federal government in league with non-slaveholding states to eliminate the institution of slavery and destroy the economy and lifestyle of the South.