Caddo, Osage and Quapaw Native Americans had permanent settlements here when Spaniard Hernando de Soto visited in the mid-1500s. Frenchman Henri de Tonti founded the first white settlement in 1686. After the 1803 Louisiana Purchase, Arkansas became a US territory, and slaveholding planters moved into the Delta to grow cotton. Poorer immigrants from Appalachia settled in the Ozark and Ouachita plateaus.
On the edge of the frontier, lawlessness persisted until the Civil War. From 1863 the northern part of the state was occupied by Union troops. Reconstruction was difficult, and development only came after 1870 with the expansion of railroads. Racial tension peaked in 1957, when the federal government intervened to enforce the integration of Arkansas schools. The state has one of the lowest per-capita incomes in the US, with many poor African Americans in the Delta and poor whites in the Ozarks.