A state of the southern United States on the Gulf of Mexico. It was admitted as the 18th state in 1812. Part of the vast region claimed by La Salle for France in 1682, it was settled by the French in the early 1700s. Control of the area passed to the United States in 1803, and the Territory of Orleans was created in 1804 when the northern part was split off to form the District of Louisiana (later the Territory of Louisiana and the Missouri Territory). Baton Rouge is the capital.