In the contentious election of 1860, Republican Abraham Lincoln was elected President without receiving a single electoral vote from a Southern state. After his election, but before he took office, seven Southern states seceded from the Union: South Carolina, Mississippi, Florida, Alabama, Georgia, Louisiana, and Texas.
On March 4, 1861, Chief Justice Roger Brooke Taney issued the oath of office to Lincoln. During his inaugural address, Lincoln assured the remaining slave states, which had not yet seceded, that he would not disturb their institutionalized slavery. His promises, however, would not be effective. On April 12, 1861, Confederate forces fired on Fort Sumter in South Carolina. Unable to receive federal reinforcements, the fort was surrendered three days later. Soon, the slave states of Virginia, North Carolina, Tennessee, and Arkansas joined the Confederacy.
Though the conflict is called the Civil War, Congress never formally voted on a declaration of war. Rather, President Lincoln prosecuted the military campaign through broad and largely unprecedented assertions of executive powers. Ex Parte Merryman (1861), decided by Taney, considered whether the President could deny a prisoner the right to ask a judge to determine the legality of his confinement.