James Buchanan (Wikipedia) James Buchanan Jr. (/bjuːˈkænən/ bew-KAN-ən; April 23, 1791 – June 1, 1868) was the 15th president of the United States, serving from 1857 to 1861. Buchanan also served as the secretary of state from 1845 to 1849 and represented Pennsylvania in both houses of the U.S. Congress. He was an advocate for states’ rights, particularly regarding slavery, and minimized the role of the federal government preceding the Civil War.