Chivalry and Betrayal: The Hundred Years' War to confirm his legitimacy resumed the war with France now led by a king who was insane. In 1415 he landed at Harfleur which fell after a long siege weakening the English army. Against advice Henry led his army on a chevauchée to English held Calais but was intercepted by a far larger French army at Agincourt and at the ensuing battle Henry's archers killed the cream of French nobility. At Agincourt Henry V, the son of a usurper, had proved his right to be King and he was determined to regain Normandy and recreate the Duchy and landed in
English longbow in England in the period between the Norman conquest and the reign of Edward III, but that powerful longbows shooting heavy arrows were a rarity until the later 13th century. Whether or not there was a technological revolution at the end of the 13th century therefore remains in dispute. What is agreed, however, is that the English longbow as an effective weapon system evolved in the late 13th and early 14th centuries. The longbow decided many medieval battles fought by the English and Welsh, the most significant of which were the Battle of Crécy (1346) and the Battle of Agincourt