Edward did not invade France for some years, but his sailors destroyed the French fleet and began to show themselves able to maintain their king's claim to be lord of the English seas upon every side. In 1346 Edward himself landed in Normandy, devastated the country, and marched up the Seine almost to Paris, but was then obliged to retreat northward before a large army which Philip had collected. Edward made a halt at Crécy, and here one of the most celebrated battles of history took place. It taught the world a great lesson in warfare by proving once more, as the battle of Bannockburn had already done, that foot soldiers, properly armed and trained to act in concert, could defeat the feudal cavaliers in spite of their lances and heavy armor. The proud mounted knights of France performed prodigies of valor, each for himself, but they did not act together and could not hold their ground against the deadly shower of arrows poured into their midst from the long bows of the English archers. The flower of French chivalry was routed with terrible slaughter by the serried ranks of the humble English foot soldiers.[180] It was at Crécy that Edward's son, the Black Prince,--so named from his black armor,--won his spurs.[181] [Sidenote: The English take Calais.] [Sidenote: The Black Prince wins a second great victory at Poitiers, 1356.] After this great victory the English king proceeded to lay siege to Calais, the French coast town nearest England. This he took, drove out a great part of the inhabitants, and substituted Englishmen for them. The town remained subject to England for two centuries. When the war was renewed the Black Prince, now at the height of his fame, was able to deal the enemy a still more crushing blow than at Crécy. He again put the French knights to flight in the battle of Poitiers; he even captured the French king, John, and carried him off to London. [Sidenote: The Estates General attempt to control the king and reform the government.]