Fort Scott stood at the center of major developments in the nation's growth, from the forced relocation of eastern Native American tribes west of the Mississippi River to the conflicts over slavery in Kansas and the Civil War. Established in 1842 and named after General Winfield Scott, it was one of several forts that enforced the so-called permanent Indian frontier in what was then unorganized territory, keeping white settlers out and helping maintain peace among relocated tribes such as the Miami, New York Indians, Potawatomi, and Ottawa and local tribes such as the Osage. It typically housed both infantry and dragoons, and during the 1840s its dragoons also helped keep peace along the Santa Fe and Oregon trails. From 1846 to 1848, most of its troops left to fight in the Mexican-American War, and the territorial gains that followed weakened the idea of a permanent Indian frontier. The army closed Fort Scott shortly before Kansas Territory opened to Euro-American settlement in 1854, and the remaining buildings were sold in 1855, forming the nucleus of the City of Fort Scott. As conflict over slavery intensified after the Kansas-Nebraska Act of 1854, Fort Scott became deeply divided, with the town largely supporting slavery while Free-Staters and abolitionists lived nearby. Violence during Bleeding Kansas repeatedly brought soldiers in to restore order in 1858 and 1859, until anti-slavery sentiment ultimately prevailed and Kansas entered the Union as a free state in 1861. During the Civil War, the U.S. Army returned to Fort Scott to establish a military base, supply troops, and protect Kansas from Confederate forces. Fort Scott also served as a hospital and refuge for Native Americans, escaped slaves, and farmers displaced by the fighting, and many refugees joined the army, including the First Kansas Colored Volunteer Infantry, the first African American regiment to fight the Confederacy. After the war, Fort Scott pursued railroad connections to eastern markets, and when the Missouri River, Fort Scott, and Gulf Railroad reached the city by 1869, the military established the Post of Southeast Kansas from 1869 to 1873 to protect railroad workers and business interests amid conflict with squatters.