By 1420, the French were broken. The Treaty of Troyes was one of the most astonishing documents in medieval history: Henry V was named heir to the French throne, disinheriting the Dauphin (the French prince). He married Catherine of Valois, the French king’s daughter. For a brief, brilliant moment, it seemed that England and France would be united under one crown. But history is cruel to conquerors. Henry V never sat on the throne of France. While campaigning against holdouts loyal to the Dauphin, he fell ill—likely with dysentery—at the siege of Meaux. He died on August 31, 1422, at the age of just 35.
Henry’s claim to the French throne was tenuous at best, based on distant ancestry from Edward III. But in an age where God’s favor was proven on the battlefield, Henry believed that a successful invasion would silence his domestic critics and crown him the rightful King of France. On August 11, 1415, Henry sailed for France. After the siege of Harfleur—a bloody affair that cost him thousands of men to dysentery—he decided on a desperate gamble. Rather than sail home in disgrace, he marched his exhausted, starving army 150 miles across northern France toward the safety of Calais. Henry V
By nightfall, the English had lost perhaps 400 men. The French lost over 6,000, including three dukes and countless nobles. Agincourt became the defining victory of the Hundred Years’ War. After Agincourt, Henry did not rest. Between 1417 and 1419, he methodically conquered Normandy—town by town, castle by castle. He learned to conduct siege warfare as deftly as he fought open battles. Rouen fell after a brutal six-month siege, where Henry famously refused to let the starving French citizens leave the city, forcing them to eat horses, dogs, and eventually grass before surrender. By 1420, the French were broken