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.