The principal village of the Wichita in the 1830s had been near the Wichita Mountains of Oklahoma, although the Tawakoni and Wacos, who still lived in Texas, had been moved onto a reservation on the upper Brazos River.

They are forced out of Texas to a reservation in Oklahoma in 1859.

During the Civil War, the Wichita ally with the Union side.

They move to Kansas, where they establish a village at the site of present-day Wichita, Kansas.

Growing sectional conflict over slavery erupts into the small civil war known as “Bleeding Kansas” (1854-59), which serves as a grim dress rehearsal for the American Civil War (1861-1865).

Kansas, erroneously described in 1806 by the explorer Zebulon M. Pike as the “great American Desert”, had been thoroughly explored during the first half of the 19th century, but westward-bound settlers and miners had passed through it without staying.

Sparsely settled by Euramericans, principally antislavery New Englanders of Anglo-Saxon stock, the region is home to five Amerindian nations as well as twenty tribes that the U.S. government has relocated to the territory.

With the passage of the Kansas-Nebraska Act of 1854, Leavenworth, first settled in 1827 by Colonel Henry H. Leavenworth to protect travelers on the Santa Fe Trail, becomes the territorial capital of Kansas; Andrew Reeder is the first territorial governor.

The rush to populate the new territory begins, and Kansas becomes a major breeding ground for the sectional conflict as North and South each attempt to send the most settlers into the new territory.

The Kansas-Nebraska Act of 1854 creates two territorial governments designed to ease the construction of the Central Pacific Railroad, itself a compromise between the anti-slavery forces who favor a Northern Pacific Line and the South’s insistence on a Southern Pacific route (which results in the Gadsden Purchase).

To gain the necessary support, the Kansas-Nebraska legislation means allowing slavery into both territories.

Anti-slavery northerners pour in to settle Kansas, but pro-slavery thugs from Missouri take over the polls, enabling the passage of a state constitution allowing slavery.

Terrorist activities escalate on both sides as the constitution awaits ratification.

President James Buchanan, in an attempt to maintain the Union, approves the constitution, as does the Senate, but the House links its approval to a favorable referendum.

The eastern Kansas city of Lawrence, named for New England textile manufacturer Amos A. Lawrence, is founded along the Kansas (Kaw) River in 1854 by antislavery radicals.

The founders have come to Kansas under the auspices of the New England Emigrant Aid Company to outvote proslavery settlers and thus make Kansas a nonslave state.

The Republican Party in the United States is founded on February 28, 1854, by abolitionists, modernizers, ex-Whigs and ex-Free Soilers.

The Republican Party will quickly become the principal opposition to the dominant Democratic Party and the briefly popular Know Nothing Party.

The main cause is opposition to the Kansas–Nebraska Act, which repeals the Missouri Compromise by which slavery is kept out of Kansas.

The Northern Republicans see the expansion of slavery as a great evil.

The first public meeting of the general anti-Nebraska movement, at which the name Republican is suggested for a new anti-slavery party, is held in a schoolhouse in Ripon, Wisconsin.

The name is partly chosen to pay homage to Thomas Jefferson's Republican Party.

The Kansas–Nebraska Act becomes law (replacing the Missouri Compromise of 1820) on May 30, 1854, creating the Kansas Territory and the Nebraska Territory, west of the State of Missouri and the State of Iowa.

The Kansas–Nebraska Act also establishes that these two new Territories will decide either to allow or disallow slavery, depending on balloting by their residents (these areas would have been strictly "free territory" under the Missouri Compromise, which allowed slavery in the State of Missouri but disallowed it in any other new state north of latitude 36° 30', which forms most of the southern boundary of Missouri.

This prohibition of slavery extends all the way from the western boundary of Missouri to the Pacific Ocean).

Kansas, passed to the United States as a part of the Louisiana Purchase in 1803, has since 1830 been in an area designated as Indian Territory, where the U.S. government has relocated tribes who occupy lands wanted by Euramericans.

On May 30, 1854, the U.S. Congress passes Senator Stephen A. Douglas's Kansas-Nebraska Act, which repeals the prohibition of slavery north of latitude 36°0' (established in the Missouri Compromise of 1820).

Kansas is organized as a territory, including most of the eastern half of present-day Colorado.

In a break with precedent, Congress allows the territory's citizens to determine the slavery question for themselves.

This most crucial application of the doctrine of “popular sovereignty” (called Squatter Sovereignty by its detractors) makes slavery legally possible in a vast new area.

Eli Thayer of Worcester, Massachusetts, founds the Massachusetts Emigrant Aid Society in 1854 to promote the settlement of anti-slavery groups in Kansas with the ultimate objective of making it a free state.

Thayer had founded Worcester’s Oread Institute, a school for young women, in 1848.

The name appeals to those who recall Jeffersonian “republicanism” and generally place the national interest above sectional interest and above states' rights.

The party's founders, having specifically created it as an engine to oppose the westward extension of slavery, are firmly linked in common opposition to slavery, particularly to the recent passage of the Kansas-Nebraska Act of 1854, which will potentially extend slavery into these newly created territories.

White squatters continue to be a frequent problem for the Osage, but they recover from population losses, regaining a total of five thousand members by 1850.

The Kansas–Nebraska Act results in numerous settlers arriving in Kansas from 1854; both abolitionists and pro-slavery groups are represented among those trying to establish residency in order to vote on whether the territory will have slavery.

The Osage lands have become overrun with European-American settlers.

In 1855, the Osage suffer another epidemic of smallpox, because a generation had grown up without getting vaccinated.