Louisiana Louisiana Louisiana (, ) is a state in the Deep South region of the southeastern United States. It is the 31st most extensive and the 25th most populous of the 50 United States. Louisiana is bordered by Arkansas to the north, Mississippi to the east, the Gulf of Mexico to the south, and the state of Texas to the west. A large part of its eastern boundary is demarcated by the Mississippi River. Louisiana is the only U.S. state with political subdivisions termed parishes, which are equivalent to counties. The state's capital is Baton Rouge, and its largest city is
Louisiana State Capitol and the remaining territory east of the Mississippi was turned over to Great Britain. The French reclaimed Louisiana from the Spanish in 1803 after the Treaty of San Ildefonso in 1800; the territory was then sold as the Louisiana Purchase to the United States. The ceremonial transfers of Louisiana from Spain to France took place in front of the colonial seat of government, the Cabildo, in November 1803, with the transfer from France to the U.S. occurring there, as well, less than a month later. New Orleans continued to be the location of the capital of the Territory of Orleans,