Learn more about President James Buchanan at Wikipedia.
As President, Buchanan allied with the South in attempting to gain the admission of Kansas to the Union as a slave state under the Lecompton Constitution. In the process, he alienated both Republican abolitionists and Northern Democrats, most of whom supported the principle of popular sovereignty in determining a new state’s slaveholding status. He was often called a “doughface”, a Northerner with Southern sympathies, and he fought with Stephen Douglas, the leader of the popular sovereignty faction, for control of the Democratic Party. Buchanan’s efforts to maintain peace between the North and the South alienated both sides. Buchanan indicated in his 1857 inaugural address that he would not seek a second term; he kept his word, and supported Vice President John C. Breckinridge in 1860. In a four-way contest, Republican nominee Abraham Lincoln was declared the winner, on a platform of keeping slavery out of all Western territories. In response, seven Southern states declared their secession from the Union, eventually leading to the American Civil War. Buchanan’s view was that secession was illegal, but that going to war to stop it was also illegal, and so didn’t confront the new polity militarily. Buchanan, an attorney, was noted for his mantra, “I acknowledge no master but the law.”