Leavenworth, founded in 1854, was the first city incorporated in the territory of Kansas. The city developed south of
 Fort Leavenworth, which was established as Cantonment Leavenworth in 1827 by Colonel Henry Leavenworth.  Its location
 on the Missouri River attracted refugee African-American slaves in the antebellum years, who were seeking freedom from
 the slave state of Missouri across the river. Abolition supporters helped them find refuge.  In the years before the American
 Civil War, Leavenworth was a hotbed of anti-slavery and pro-slavery agitation, often leading to open physical confrontations
 on the street and in public meetings.

 On April 3, 1858, the "Leavenworth Constitution" for the state of Kansas was adopted here. Although the federal government
 never approved this early version of the state constitution, it was considered one of the most radical of the four constitutions
 drafted for the new territory because it recognized freed blacks as citizens.

 Refugee African Americans continued to settle in the city during the war. By 1865 it had attracted nearly one-fifth of the
 12,000 blacks in the state.  In 1866, the 10th Regiment of Cavalry, an all-black unit within the U.S. Army, was stood up at
 Fort Leavenworth.  Charles Henry Langston was an African-American leader from Boston who worked and lived in
 Leavenworth and northeast Kansas in the Reconstruction era and afterward. In Kansas, Langston worked for black suffrage
 and the right of African Americans to sit on juries, testify in court, and have their children educated in common schools.
 African Americans gained suffrage in 1870 after passage of the federal 15th constitutional amendment, and the legislature
 voted for their right to sit on juries in 1874.
 
 African Americans continued to migrate to the state of Kansas after the war. There were a total of 17,108 African Americans
 in Kansas in 1870, with 43,107 in 1880, and 52,003 by 1900. Most lived in urban areas.