England's trade, its war finance and its ability to bring force to bear against France were heavily reliant on seaborne transportation, especially to its territory in Gascony. With its own ability to raise and support a fleet much reduced by English activities, the French hired Castilian ships to blockade English ports. Frustrated by their effectiveness, Edward III himself led the fleet that intercepted them and inflicted heavy losses. In spite of that success, English trade and ports saw little relief from naval harassment by the French and their allies.