Tuscaloosa is a city in and the seat of Tuscaloosa County in west central Alabama. Located on the Black Warrior River at the Atlantic Seaboard fall line of the Piedmont, it is the fifth-largest city in Alabama, with an estimated population of 99,543 in 2016. Incorporated as a town on December 13, 1819, it was named after Tuskaloosa, the chieftain of a Muskogean-speaking people who battled and was defeated by forces of Spanish explorer Hernando de Soto in 1540 in the Battle of Mabila. It served as Alabamas capital city from 1826 to 1846. Tuscaloosa is the regional center of industry, commerce, healthcare, and education for the area of west-central Alabama known as West Alabama. It is the principal city of the Tuscaloosa Metropolitan Statistical Area, which includes Tuscaloosa, Hale and Pickens counties and has an estimated metro population in 2013 of 235,628. Tuscaloosa is also the home of The University of Alabama, Stillman College and Shelton State Community College. While the city attracted international attention when Mercedes-Benz announced it would build its first automotive assembly plant in North America in Tuscaloosa County, the University of Alabama remains the dominant economic and cultural engine in the city. Tuscaloosa has been traditionally known as the "Druid City" because of the numerous water oaks planted in its downtown streets since the 1840s. The city has also become known nationally for the University of Alabamas success in sports, and particularly in football. City leaders adopted the moniker "The City of Champions" after the Alabama Crimson Tide football team won the BCS National Championship in their 2009, 2011, and again in their 2012 seasons. The Tide won the College Football Playoff in the 2015 season. In 2008, the City of Tuscaloosa hosted the USA Olympic Triathlon trials for the Beijing Games. In recent years, Tuscaloosa has been named the "Most Livable City in America," one of Americas "100 Best Communities for Young People," one of the "50 Best College Towns," and one of the "Best Places to Launch a Small Business."