The slave – owners put forward a demand for secession , i.e. , they demanded the right for any state to withdraw from the Union . In November 1860 a congress of slave – owners in Charleston decided to secede and in December the state of South Carolina proclaimed its secession from the Union . South Carolina was followed by 10 other slave states . The action of the ” poor whites ” against the secession was most savagely suppressed by the slave – owning planters . The Southern Confederacy was formed at the Congress of six seceded states in Montgomery ( Alabama ) in February 1861 and Jefferson Davis , a rich planter and rabid advocate of slavery , was elected its president . The city of Richmond ( capital of Virginia ) was proclaimed the capital of the Con federacy . The temporary Constitution of the Confederate States of America adopted by the Congress proclaimed slavery a ” natural state ” and ” bulwark of civilisation ” . In April 1861 the troops of the South attacked Fort Sumter ( near Charleston , South Carolina ) which had remained loyal to Lincoln’s government . Thus began the American Civil War which lasted four years ( 1861-65 ) .