The Kansas–Nebraska Act of 1854 created the territories of Kansas

Kansas Territory

The Territory of Kansas was an organized incorporated territory of the United States that existed from May 30, 1854, until January 29, 1861, when the eastern portion of the territory was admitted to the Union as the State of Kansas....

 and Nebraska

Nebraska Territory

The Territory of Nebraska was an organized incorporated territory of the United States that existed from May 30, 1854, until March 1, 1867, when the final extent of the territory was admitted to the Union as the State of Nebraska. The Nebraska Territory was created by the Kansas–Nebraska Act of 1854...

, opening new lands for settlement, and had the effect of repealing the Missouri Compromise

Missouri Compromise

The Missouri Compromise was an agreement passed in 1820 between the pro-slavery and anti-slavery factions in the United States Congress, involving primarily the regulation of slavery in the western territories. It prohibited slavery in the former Louisiana Territory north of the parallel 36°30'...

 of 1820 by allowing settlers in those territories to determine through Popular Sovereignty

Popular sovereignty

Popular sovereignty or the sovereignty of the people is the political principle that the legitimacy of the state is created and sustained by the will or consent of its people, who are the source of all political power. It is closely associated with Republicanism and the social contract...

 if they would allow slavery within each territory. The act was designed by Democratic

History of the United States Democratic Party

The history of the Democratic Party of the United States is an account of the oldest political party in the United States and arguably the oldest democratic party in the world....

 Senator Stephen A. Douglas

Stephen A. Douglas

Stephen Arnold Douglas was an American politician from the western state of Illinois, and was the Northern Democratic Party nominee for President in 1860. He lost to the Republican Party's candidate, Abraham Lincoln, whom he had defeated two years earlier in a Senate contest following a famed...

 of Illinois

Illinois

Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

. The initial purpose of the Kansas–Nebraska Act was to open up many thousands of new farms and make feasible a Mideastern Transcontinental Railroad

Transcontinental railroad

A transcontinental railroad is a contiguous network of railroad trackage that crosses a continental land mass with terminals at different oceans or continental borders. Such networks can be via the tracks of either a single railroad, or over those owned or controlled by multiple railway companies...

.