Notwithstanding many treaties which had taken place, and the near alliance which had been well-nigh carried out between the royal families of England and Spain, Spanish pirates had never ceased to carry on a series of aggressions upon the English vessels trading in the Bay of Biscay. Ships were every day taken, and the crews cruelly butchered in cold blood. Edward's remonstrances proved vain, and when threats of retaliation were held out by Edward, followed by preparations to carry those threats into effect, Pedro the Cruel, who had now succeeded to the throne of Spain, dispatched strong reënforcements to the fleet which had already swept the English Channel. The great Spanish fleet sailed north, and capturing on its way a number of English merchantmen, put into Sluys, and prepared to sail back in triumph with the prizes and merchandise it had captured. Knowing, however, that Edward was preparing to oppose them, the Spaniards filled up their complement of men, strengthened themselves by all sorts of the war machines then in use, and started on their return for Spain with one of the most powerful armadas that had ever put to sea. Edward had collected on the coast of Sussex a fleet intended to oppose them, and had summoned all the military forces of the south of England to accompany him; and as soon as he heard that the Spaniards were about to put to sea he set out for Winchelsea, where the fleet was collected. The queen accompanied him to the sea-coast, and the Black Prince, now in his twentieth year, was appointed to command one of the largest of the English vessels. The fleet put to sea when they heard that the Spaniards had started, and the hostile fleets were soon in sight of each other. The number of fighting men on board the Spanish ships was ten times those of the English, and their vessels were of vastly superior size and strength. They had, moreover, caused their ships to be fitted at Sluys with large wooden towers, which furnished a commanding position to their cross-bowmen. The wind was direct in their favor, and they could have easily avoided the contest, but, confiding in their enormously superior force, they sailed boldly forward to the attack.