Since the Norman Conquest of 1066, English monarchs had held titles and lands within France, the possession of which made them vassals of the kings of France. By 1337 only Gascony in south western France and Ponthieu in northern France were left.[2] The Gascons preferred their relationship with a distant English king who left them alone, to one with a French king who would interfere in their affairs.[3] 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.[4]
Before the war commenced at least 1,000 ships a year departed Gascony. Among their cargoes were over 80,000 tuns of wine.[5][note 1] The duty levied by the English Crown on wine from Bordeaux, the capital of Gascony, was more than all other customs duties combined and by far the largest source of state income. Bordeaux had a population of over 50,000, greater than London's,[7] and Bordeaux was possibly richer. However, by this time English Gascony had become so truncated by French encroachments that it relied on imports of food, largely from England. Any interruptions to regular shipping were liable to starve Gascony and financially cripple England; the French were well aware of this.[8] Although Gascony was the cause of the war, Edward was able to spare few resources for it, and previously when an English army had campaigned on the continent it had operated in northern France. In most campaigning seasons the Gascons had had to rely on their own resources and had been hard pressed by the French.[9][10] In 1339 the French besieged Bordeaux, the capital of Gascony, even breaking into the city with a large force before they were repulsed.[11] Typically the Gascons could field 3,000–6,000 men, the large majority infantry, although up to two-thirds of them would be tied down in garrisons.