James Buchanan was the last American president born in the 18th century, and his term (1857-61) was the last before the Civil War. Buchanan came to the presidency after a distinguished public career: 10 years as a U.S. representative and another 10 as a senator, ambassadorships to both Russia and Great Britain, and service as James K. Polk's secretary of state. In the 1856 elections he whipped both former president Millard Fillmore and frontier hero John C. Fremont, no small feat. But as president Buchanan couldn't handle the bad blood between North and South; his attempts to find a legalistic solution were never effective. By the election of 1860 Buchanan was tired of the presidency and did not seek re-election. Rightly or wrongly, "Old Buck" has been tagged as one of history's least effective presidents. He was succeeded by Republican Abraham Lincoln.
Buchanan was a lifelong bachelor and the only president never to marry… His vice-president, John Cabell Breckinridge of Kentucky, was the youngest ever: just over 36 years old when he was inaugurated.