sentences:  Following a series of disagreements between Philip VI of France () and Edward III of England (), on 24 May 1337 Philip's Great Council in Paris agreed that the Duchy of Aquitaine, effectively Gascony, should be taken back into Philip's hands on the grounds that Edward was in breach of his obligations as a vassal.This marked the start of the Hundred Years' War, which was to last 116 years.Although Gascony was the cause of the war, Edward was able to spare few resources for it and when an English army had campaigned on the continent it had operated in northern France.