Edward III reopened hostilities with France in 1337, although he did not officially claim the French throne by right of descent from Philippe IV until 1340, quartering the French lilies with the leopards of England on his coat of arms. Despite early setbacks, mostly financial, Edward's military campaigns were brilliantly successful, beginning with the destruction of a large French fleet at Sluys in 1340, and culminating in the defeat of Philippe of Valois's army at Crécy in August 1346 and the taking of Calais a year later. The war was both politically and economically successful; the resettlement of Calais by the English created an easily-reached trading bridgehead in northern France, and strategically it provided a base for the patrolling of the Channel against pirates and potential invaders. On a less exalted level, the general ransoming and looting which accompanied Edward's French campaigns made fortunes for some at the enemy's expense. However, the success at Calais was followed by the catastrophe of the bubonic plague. This was, of course, a European, not simply an English, disaster, but for a nation which had achieved so much since 1340, it must have seemed doubly catastrophic, and also difficult to understand. Edward III evacuated Calais in August 1347, and the plague arrived in England exactly a year later. It spread to London, then to Norwich, then northwards, dying down in the winter of 1349.