Who was the president at the beginning of the civil war?
Abraham Lincoln had just been elected US President when the Southern states that would become united as the Confederate States of America seceded. According to Wikipedia, part of the reason for secession was due to the South's concerns that Lincoln would abolish slavery entirely. Since Lincoln had not been inaugurated when the states seceded, though, James Buchanan was technically President at the very start. Jefferson Davis was president of the Confederacy.