The first Colonizers to occupy the area of the present-day state were French colonists, followed later by Spanish and English colonists, particularly along the Gulf Coast. Euro-Americans did not enter the territory in great number until the early 19th century. Some early settlers would bring many enslaved Africans with them to serve as laborers to develop cotton plantations along major riverfronts. In 1817, Mississippi became a state of the United States. Through the 1830s, the federal government forced most of the native Choctaw and Chickasaw people west of the Mississippi River. American planters developed an economy based on the export of cotton produced by slave labor along the Mississippi and Yazoo rivers. A small elite group of planters controlled most of the richest land, the wealth, and politics of the state, which led to Mississippi seceding from the Union in 1861. During the Civil War, its river cities particularly were sites of extended battles and widespread destruction.