The 34th United States Congress was a meeting of the legislative branch of the United States federal government, consisting of the United States Senate and the United States House of Representatives. It met in Washington, D.C., from March 4, 1855, to March 4, 1857, during the last two years of Franklin Pierce's presidency. The apportionment of seats in the House of Representatives was based on the 1850 United States census. The Whig Party, one of the two major parties of the era, had largely collapsed, although many former Whigs ran as Republicans or as members of the "Opposition Party." The Senate had a Democratic majority, and the House was controlled by a coalition of Representatives led by Nathaniel P. Banks, a member of the American Party.

Bleeding Kansas, Bloody Kansas, or the Border War was a series of violent civil confrontations in Kansas Territory, and to a lesser extent in western Missouri, between 1854 and 1859. It emerged from a political and ideological debate over the legality of slavery in the proposed state of Kansas.