James Buchanan served as the 15th President of the United States from 1857 to 1861. He hurt his party in the North through several vetoes and endorsed the controversial Lecompton Constitution for Kansas. Though experienced in foreign diplomacy, Buchanan struggled to prevent the outbreak of the Civil War and find compromises to postpone it. He carried out the traditional roles of president but was ultimately unable to address the growing sectional tensions over slavery that divided the nation.