James Buchanan was born near Mercersburg, Pennsylvania, a community in the south-central part of the state, about 25 miles west of Chambersburg. His father was a successful businessman who sent his son to local schools. Buchanan graduated from Dickinson College in 1809. 
Buchanan was admitted to the bar in 1812, and quickly developed a successful practice. He entered politics in 1814, and served in the state legislature. He developed a reputation as an excellent public speaker. Buchanan was involved in an unfortunate love affair in which his fiancée broke off the engagement and died shortly thereafter; Buchanan would never marry.
Buchanan saw duty in the War of 1812. In 1821 he was elected to Congress initially as a Federalist. Later, he switched his allegiance to Andrew Jackson. Relations with the hero of New Orleans soured considerably when Buchanan was accused of playing a role in the “Corrupt Bargain," which denied Jackson the presidency in 1824.
The relationship improved and Buchanan accepted a Jackson appointment as minister to Russia in 1832-33. When he returned, he was elected to the Senate and became active in Democratic affairs and a supporter of Martin Van Buren. Buchanan had hoped for the nomination in 1844, but contented himself with serving as secretary of state for James K. Polk. The Oregon boundary question was successfully resolved, but the Slidell Mission was a failure. From 1853 to 1856, Buchanan was the minister to Britain for the Pierce administration; he weakened his reputation in some quarters in the Ostend Manifesto fiasco, although he gained support from Southerners.
Buchanan’s triumph in the Election of 1856 thwarted the plans of the new Republican Party, but the new president was hated by many in the North and trusted by few in the South. Buchanan objected to slavery on moral grounds, but believed the institution was protected by the Constitution.
In his first year Buchanan had to deal with the Panic of 1857 and the resulting depression. He proclaimed that the Dred Scott decision would offer a final solution to the issue of extending slavery to the territories, but his assessment was wrong. He lost further support in the North by advocating acceptance of the Lecompton constitution, clearly a minority document, in the "Bleeding Kansas" drama.
Buchanan’s refusal to support Stephen A. Douglas in 1860, helped to split the Democratic Party and open the door for Abraham Lincoln. Neither faction of the Democrats nominated Buchanan, who became a bystander in the Election of 1860. After the election, Buchanan still had to face the emerging secession crisis for four months until Lincoln's scheduled inauguration in March. His response was inaction, believing that secession was illegal, but armed efforts to prevent states from leaving the Union were also without sanction.
Part of Buchanan's problem was that his cabinet was riddled with Southerners who sympathized with the Confederacy. His Secretary of War was a Virginia slaveholder, who ordered the armories in the South to transfer arms and ammunition to the CSA.
Writing on the same day that the Crittenden Compromise was defeated in the Senate, John Sherman, brother of William Tecumseh Sherman and the author much later of the Sherman Anti-Trust Act, expressed the disappointment bordering on outrage that Republicans felt during the last months of the Buchanan administration:
... "The Union, it must be preserved." Such would be the voice of the whole country, if the government was not now administered by those who not only permit treason but actually commit it, by turning the powers of the government against itself. They kill the government they have sworn to maintain and defend, because the people, whose agents they are, have condemned them. In this spirit we have seen a secretary of the treasury, charged with the financial credit of the government, offering for sale the bonds of the government and, at the same moment, declaring that it will be overthrown and that he would aid in overthrowing it.Buchanan did accept the advice of his Secretary of State Jeremiah S. Black that Fort Sumter should be defended. Buchanan was pleased to surrender office to Lincoln and happily settled into life on his estate, Wheatland, near Lancaster. Today Buchanan is chiefly remembered for being the president who served immediately before Lincoln, but that view ignores the fact that he had played a prominent role in public life for half a century. Buchanan has been roundly criticized for his lack of response to the secession crisis, but it should be remembered that there existed a long tradition of compromise on the thorny sectional issues. Buchanan was simply trying to do what others before him had done. James Buchanan was a capable public servant trying to govern in times that required genius.