Castillon-la-Bataille (kästēyôNˌ-lä-bätäˈyə) [key], town (1993 est. pop. 3,030), Gironde dept., SW France, in Guienne, on the Dordogne River. An ancient port, it has a wine and liqueur trade and a leather industry. There, in 1453, the French defeated the English in the final great battle of the Hundred Years War. It was formerly called Castillon or Castillon-et-Capitourlan.