As Eustace saw the Dover ships apparently standing over to Calais, he came to the not wholly unnatural conclusion that their plan was to plunder the town in his absence. He laughed, for he knew that he had left it well protected. But the intention of Hubert de Burgh was incomparably more courageous and more effective. He had begun, as every English admiral in after time was wont to begin, by manoeuvring to secure the windward position, which with sailing ships gives him who holds it the option of attack. As soon as the French vessels had been brought well to leeward, the English turned together before the wind, and, forming what in after times would have been called the line abreast, stood at their utmost speed in pursuit of the enemy. The Monk was completely out-manoeuvred. His heavily-laden vessels could not escape pursuit by flight, while they must infallibly be thrown into confusion by the act of turning to face the pursuers. It was no small advantage to the English that their arrows would fly with the wind. So soon as they were within shot, Hubert de Burgh's archers let fly, and the clothyard shafts, or the bolts from the crossbows, came whistling down on the crowded benches of the French ships. All battles then by land or sea were settled at close quarters with cold steel. The English pressed on to board. Where the enemy's ships were caught in the act of turning, they drove into them with the stem, ramming and sinking them. When this more expeditious method could not be practised, the English laid the enemy aboard, throwing quicklime, which the wind blew in the Frenchmen's faces, into the air in the moment of impact. The boarders followed close on the blinding cloud, and the axes of the Cinque Ports men fell briskly to work.
"Whenas he fights and has the upper hand By sea he sends them home to every land,"
wrote Chaucer of the shipman. The Cinque Ports men, who had had a cruel experience of the tender mercies of John's foreign mercenaries, were certainly in no humour to give quarter to the adventurers who were on their way to England to renew the worst excesses of the wicked king's followers. There was a great massacre. Taken at a disadvantage, and scattered at the moment of attack, the Monk's ships were overpowered in detail. So great was the fury of the English crews that it overcame even the love of ransom which commonly introduced some measure of mercy into mediæval battles. Eustace himself, who, we are told, offered a great price for his life, was beheaded by one blow of the sword by Richard, King John's bastard son. The whole fleet on which Louis and the barons had relied to save them from destruction, was annihilated. The neck of the opposition to the young king's government was effectually broken. Before the end of the year Louis had returned to France, and the barons had made their submission.