"As early as 1858, the ongoing conflict between the North and South over the issue of slavery had led Southern leadership to discuss a unified separation from the United States. By 1860, the majority of the slave states were publicly threatening secession if the Republicans, the anti-slavery party, were elected to the presidency. Following Lincoln's victory over the divided Democratic Party on November 7, South Carolina immediately initiated secession proceedings and, on December 20, its legislature passed the "Ordinance of Secession," which declared that "the Union now subsisting between South Carolina and other states, under the name of the United States of America, is hereby dissolved." After the declaration, South Carolina set about seizing forts, arsenals, and other strategic locations within the state."
"When Abraham Lincoln was inaugurated on March 4, 1861, six more states (Mississippi [1/9], Florida [1/10], Alabama [1/11], Georgia [1/19], Louisiana [1/26], Texas [2/1]) had formally seceded from the Union, and federal troops held only Fort Sumter in South Carolina, Fort Pickens off the Florida coast, and a handful of minor outposts in the South. On April 12, 1861, the American Civil War began when Confederate shore batteries under General P. G. T. Beauregard opened fire on Fort Sumter in South Carolina's Charleston Harbor."