The Hundred Years' War

In 1337 Edward III of England claimed the French throne through his mother, and England and France fought on and off for 116 years. On its battlefields the medieval order died: at Crécy and again at Agincourt in 1415, English longbowmen — commoners — cut down the armored French nobility who had dominated war for 700 years, and by the end gunpowder cannon were knocking down the castles that had made lords untouchable. France was nearly lost until Joan of Arc, a teenage peasant claiming divine instruction, rallied its armies at Orléans in 1429; the English burned her as a heretic two years later, and lost anyway. Out of the long agony, England and France each began to congeal into something new — nations defined against each other rather than collections of a king's inherited lands.