Lafayette (/lɑːfaɪˈɛt/; French: [lafajɛt]) is a city located along the Vermilion River in southwestern Louisiana. The city of Lafayette is the fourth-largest in the state, with a population of 120,623 at the 2010 census. The combined statistical area of Lafayette–Opelousas-Morgan City was 611,774 according to 2012 estimates. Lafayette is the parish seat of Lafayette Parish, Louisiana.

The European-American city was founded as Vermilionville in 1821 by Jean Mouton, a French-speaking man of Acadian descent. In 1884, it was renamed for General Lafayette, who fought with and significantly aided the American Army during the American Revolutionary War. The city's economy was primarily based on agriculture until the 1940s, when the petroleum and natural gas industries became dominant. Lafayette is considered the center of Acadiana, the area of Cajun culture in Louisiana and the United States. It developed after Acadians were relocated here following their expulsion by the British from eastern Canada in the late 18th century following the defeat of France in the Seven Years' War. There is also a Louisiana Creole influence in the area. Most Creoles of color and their descendants originated to the east in New Orleans, descendants first of French colonists and African slaves, then a third class of free people of color, French speaking and Catholic.