More than a thousand English soldiers were killed by hailstones during the Siege of Chartres in 1360.
In war, weather can turn the victor into the vanquished startlingly quickly. (Just ask the Spanish Armada or Napoleon’s Grand Armée.) The Edwardian phase of the Hundred Years’ War ended in 1360, and its conclusion turned on a single devastating hailstorm.
King Edward III of England had designs on the throne of France. Edward’s son had captured the French king at the Battle of Poitiers in 1356. The chaos that ensued left France vulnerable, and Edward attempted to capitalise on that vulnerability. He assembled an army of ten thousand men, huge by 14th century standards, and marched them across the French countryside.
First the army went to Rheims, where French kings were traditionally crowned. But Rheims was too well fortified, so Edward set out for Paris instead. He hoped to provoke the king’s son (and acting leader of France) into battle, but the canny dauphin did not bite and once again the English army had to move along.
Their final stop: Chartres. Edward’s army laid siege to the city on Easter Monday, 1360. That night, an April storm hit. Lightning, freezing rain, and then enormous lethal hailstones. Men scattered, horses stampeded, the camp was destroyed, and when dawn rose it became apparent that the army had been literally decimated. Of the original ten thousand, a full thousand men had died (along with six thousand horses, apparently) – from the lightning, the hail, and the ensuing chaos. One of the army’s commanders, Sir Guy de Beauchamp, was seriously injured; he died a few weeks later.
That was the end of Edward’s quest to be the King of France. He signed a peace treaty that relinquished his claim to the throne and agreed to ransom the captive king back to his homeland. The French, in exchange, ceded large swathes of territory in the south of France. Peace reigned again… for another nine years, at least. This was, after all, only the first phase of the Hundred Years’ War.
[Thanks to Gareth E.]