Mobile is the third most populous city in the Southern U.S. state of Alabama and is the county seat of Mobile County. It is located on the Mobile River and the central Gulf Coast of the United States. The population within the city limits was 198,915 during the 2000 census. Mobile is the principal municipality of the Mobile Metropolitan Statistical Area (MSA), a region of 399,843 residents which is composed solely of Mobile County and is the second largest MSA in the state. Mobile is included in the Mobile-Daphne-Fairhope Combined Statistical Area with a total population of 540,258, the second largest combined statistical area in the state behind Birmingham. Mobile began as the first capital of colonial French Louisiana in 1702. The city gained its name from the Native American Mobilian tribe that the French colonists found in the area of Mobile Bay. During its first 100 years, Mobile was a colony for France, then Britain, and lastly Spain. Mobile first became a part of the United States of America in 1813. It then left that union in 1861 when Alabama joined the Confederate States of America, which collapsed in 1865. Located at the junction of the Mobile River and Mobile Bay on the northern Gulf of Mexico, the city is the only seaport in Alabama. The Port of Mobile has always played a key role in the economic health of the city beginning with the city as a key trading center between the French and Native Americans down to its current role as the 9th largest port in the United States. As one of the Gulf Coast's cultural centers, Mobile houses several art museums, a symphony orchestra, a professional opera, a professional ballet company, and a large concentration of historic architecture. Mobile is known for having the oldest organized Carnival celebrations in the United States, dating to the 1700s of its early colonial period. It was also host to the first formally organized Carnival mystic society or "krewe" in the United States, dating to 1830. People from Mobile are known as Mobilians.