The Château de Ranton is a small fortified castle in the village of Ranton, in the Department of the Vienne just west of Loudun, and south of the Loire. It was one of the front-line of fortresses which were built to defend the royal city of Loundun at the beginning of the Hundred Years' War in 1340–1345. It played this military role until 1372. It then became a feudal manor and one of the estates of aristocratic families associated with the Courts of the French Kings and the Dukes of Anjou.