Answer:
James Buchanan was the 15th president of the United States for four years. Many people consider him to be one of the least active or worthwhile presidents so far. He also fought in two long wars. He stood up for the constitutional rights of individuals to hold slaves. Buchanan won after a hotly contested campaign and the threat of Civil War if any of the Republicans won.
The Dred Scott court case occurred at the beginning of his administration which stated that slaves were considered property. Despite being against slavery himself, Buchanan felt that this case proved the constitutionality of slavery. He fought for Kansas to be entered into the union as a slave state but it was eventually admitted as a free state in 1861.
There was an economic depression in 1857 called (so appropriately) the Panic of 1857. The North and West were hit hard but Buchanan took no action to help alleviate the depression.
When the time came for reelection, Buchanan had decided against running again. He knew that he had lost all support, and he was unable to stop the problems that would lead to secession.
In November of 1860, Abraham Lincoln (A Republican) was elected as president immediately causing seven states to secede from the Union forming the Confederate States of America. Buchanan did not believe that the federal government could force a state to remain in the Union. Afraid of Civil War, he ignored aggressive action by the Confederate States and abandoned Fort Sumter. He left office with the union divided.