1856 Democratic National Convention in the context of "Presidency of Franklin Pierce"

John Cabell Breckinridge (January 16, 1821 – May 17, 1875) was an American politician who served as the 14th vice president of the United States, with President James Buchanan, from 1857 to 1861. Assuming office at the age of 36, Breckinridge is the youngest vice president in U.S. history. He was also the Southern Democratic candidate in the 1860 presidential election, losing to antislavery Republican candidate Abraham Lincoln.

Breckinridge was born near Lexington, Kentucky, to a prominent local family. After serving as a noncombatant during the Mexican–American War, he was elected as a Democrat to the Kentucky House of Representatives in 1849, where he took a pro-slavery stance. Elected to the U.S. House of Representatives in 1851, he allied with Stephen A. Douglas in support of the Kansas–Nebraska Act. After reapportionment in 1854 made his re-election unlikely, he declined to run for another term. He was nominated for vice president at the 1856 Democratic National Convention to balance a ticket headed by James Buchanan. The Democrats won the election, but Breckinridge had little influence with Buchanan, and as presiding officer of the Senate, could not express his opinions in debates. He joined Buchanan in supporting the proslavery Lecompton Constitution for Kansas, which led to a split in the Democratic Party. In 1859, he was elected to succeed Senator John J. Crittenden at the end of Crittenden's term in 1861.

Elections were held for the 35th United States Congress and the presidency of the United States, to serve from 1857 until 1861. The elections took place during a major national debate over slavery, with the issue of "Bleeding Kansas" taking center stage. Along with the 1854 elections, these elections occurred during the transitional period immediately preceding the Third Party System. Old party lines were broken; new party alignments along sectional lines were in the process of formation. The Republican Party absorbed the Northern anti-slavery representatives who had been elected in 1854 under the "Opposition Party" ticket (consisting largely of former Whigs) as the second-most powerful party in Congress. Minnesota and Oregon joined the union before the next election, and elected their respective congressional delegations to the 35th Congress.

In the presidential election, Democratic former Secretary of State James Buchanan defeated Republican General John Fremont and the American Party candidate, former President Millard Fillmore. Buchanan swept the South and split the North with Fremont, while Fillmore won Maryland. Buchanan had defeated incumbent President Franklin Pierce (the first elected president to lose his party's presidential nomination) and Senator Stephen A. Douglas of Illinois on the 17th ballot at the 1856 Democratic National Convention. Fremont defeated Supreme Court Justice John McLean at the 1856 Republican National Convention to take the Republican nomination. Fillmore's third-party candidacy took over twenty percent of the popular vote, the best popular vote showing by a third party until Theodore Roosevelt's 1912 candidacy.

Presidential elections were held in the United States on November 4, 1856. Democratic nominee James Buchanan defeated Republican nominee John C. Frémont and Know Nothing/Whig nominee Millard Fillmore. The main issue was the expansion of slavery as facilitated by the Kansas–Nebraska Act of 1854. Buchanan defeated President Franklin Pierce at the 1856 Democratic National Convention for the nomination. Pierce had become widely unpopular in the North because of his support for the pro-slavery faction in the ongoing civil war in territorial Kansas, and Buchanan, a former Secretary of State, had avoided the divisive debates over the Kansas–Nebraska Act by being in Europe as the Ambassador to the United Kingdom.

Slavery was the main issue, and with it the question of the survival of the United States as it then existed. The Democrats were seen as the pro-slavery party. While the new Republican party was hostile to slavery, they limited their efforts to the politically more manageable question of the extension of slavery into federal territories (and its removal from the District of Columbia). The nativist Know Nothings (known formally as the American Party) competed with the Republicans to replace the moribund Whig Party as the primary opposition to the Democrats. They emphasized opposition to Catholic immigrants.