Louisiana, the 18th state, lies on the Gulf of Mexico bounded by Texas, Arkansas, and Mississippi. The Mississippi River and its delta are the state's most important natural features. Agriculture, chemicals, and fishing are major components of the economy. New Orleans, the largest city, is a major port, and known for its colorful Mardis Gras celebration. Originally part of French North America, the area was ceded to Spain and acquired in 1803 by the United States. Creoles, descendants of the original settlers, remain prominent in the population. Louisiana also counts the "Cajuns," French-speaking Acadians expelled from Canada in 1755. A slave state prior to the Civil War, Louisiana continues to have a large African-American population.