St. Louis is the second-largest city in Missouri. It sits near the confluence of the Mississippi and the Missouri Rivers. In 2020, the city proper had a population of 301,578, while the bi-state metropolitan area, which extends into Illinois, had an estimated population of over 2.8 million, making it the largest metropolitan area in Missouri, the second-largest in Illinois, and the 20th-largest in the United States. Before European settlement, the area was a regional center of Native American Mississippian culture. St. Louis was founded on February 14, 1764, by French fur traders Gilbert Antoine de St. Maxent, Pierre Laclède and Auguste Chouteau, who named it for Louis IX of France. In 1764, following France's defeat in the Seven Years' War, the area was ceded to Spain.