On 23rd June 1340 Edward III and his fleet sighted the French fleet in the Swin off Sluys, Flanders. It would appear that rather attack directly from the North Sea the next day the English approached from the north east from the Western Scheldt through a channel behind the island of Cadzand. There they met a more powerful French fleet anchored and roped together to face an attack from the West. In the wrong orientation and unable to manoeuvre the French were wiped out in detail, loosing 190 ships (out of 202) and 16-18000 men.

Although it was a crushing victory the French galleys escaped and continued to harass southern England and English/Gascon shipping,  the naval resources of the French king still outstripped Edward's.