Gaillon is a commune in the Eure department in northern France.HistoryThe origins of Gaillon are not really known. In 892, Rollo, a Viking chief, might have ravaged Gaillon and the region, before he became the first prince of the Normans and count of Rouen in 911.The Gaillon history did begin, when the first dukes of Normandy built a keep to defend the border of Normandy against their enemies : the kings of France. The first castle of Gaillon belonged to a whole system of defence along the Norman border such as Evreux, Pacy-sur-Eure, Vernon, Malassis, Gasny, Baudemont, etc.In 1192 King Philip II Augustus of France seized the castle in his battle with Richard the Lion Heart to conquer Normandy. Richard decided to build a new one a few kilometers away in Les Andelys on the other bank of the Seine River : Château Gaillard.In 1262 the castle was exchanged between King Louis IX and Eudes Rigaud (Archbishop of Rouen) and it became the residence of the Rouen archbishops until the French Revolution.