The United States acquired Kansas in 1803 from France as part of the Louisiana Purchase. During its early years as a U.S. possession, the area was part of Indian Territory and was used by the federal government to relocate tribal peoples.
The Kansas-Nebraska Act was passed by the U.S. Congress on May 30, 1854. The Act repealed the Missouri Compromise of 1820 which prohibited slavery north of latitude 36°30´and allowed people in the territories of Kansas and Nebraska to decide for themselves whether or not to allow slavery within their borders. The Kansas-Nebraska Act infuriated many in the North who favored the Missouri Compromise, and considered it to be a long-standing binding agreement. In the pro-slavery South the new Act was strongly supported.
The passage of the Kansas-Nebraska Act was the impetus that brought Abraham Lincoln out of political retirement. Speaking in Peoria in October of 1854, Lincoln said he was willing to accept slavery where it already existed, but the spread of slavery into new territories was anathema to him. He argued that the Founding Fathers had intended for slavery to wither away, and that they intended for the nation one day to live up to the ideal professed in the Declaration of Independence that all men were created equal.
Meanwhile, both pro- and anti-slavery forces sent settlers to Kansas to influence the vote for or against slavery. Pro-slavery settlers carried the election but were charged with fraud by anti-slavery settlers, and the results were not accepted by them. The anti-slavery settlers held another election, but pro-slavery settlers refused to vote. This resulted in the establishment of two opposing legislatures within the Kansas territory.
Violence soon erupted, giving rise to the sobriquet “Bleeding Kansas.” Eventually, however, anti-slavery settlers outnumbered pro-slavery settlers and a new constitution was drawn up. On January 29, 1861, just before the start of the Civil War, Kansas was admitted to the Union as a free state.