The Kobal Collection The French had an army of 20,000, four times that of the English under King Henry V

On the dank evening of October 24, 1415, the French had every reason for confidence. Their force of 20,000 soldiers was four times that of the perfidious English invaders under King Henry V. Henry’s men were more than outnumbered. They were starving, wet and diseased. So confident, indeed, were the French of victory that they had prepared a specially painted cart in which to parade the captured English king. Alors!

At 11am the next morning, St Crispin’s Day, 1415, it rained again, but this time it rained arrows, thousands upon thousands of them, from the longbows of English and Welsh soldiers. Six hundred years ago today, the English defeated the French in the greatest military upset since David slew Goliath. It is always nice to celebrate a victory over the historic enemy, of course, but does a medieval scrap in a valley in the middle of northern France have any relevance today? Oddly, it does. The Battle of Agincourt made England; as surely as Magna Carta, the Book of Common Prayer, football and drinking tea.

The Kobal Collection 600 years ago today, the English defeated the French in the greatest battle since David slew Goliath

Ostensibly, Henry V was tramping around France to press the high-minded claim of English sovereigns to lands across the Channel as part of t he Hundred Years’ War. But Henry V was the monarch of cunning. As a prince he had been a playboy; as a ruler, he was a revelation, serious-minded and with a political vision of England as a united realm even though it was then sadly fractious. How to bring the English together? By fighting the French. At Agincourt, the French decided to oblige Hal’s nation-building scheme. The other thing about good King Henry V was that he was no military slouch.

GETTY IMAGES Lightly-clad English archers rushed forward and stabbed Frenchmen through gaps in their armour

He chose his position at Agincourt well, fighting behind muddy land at the foot of Agincourt’s wooded slope, fortifying his position with sharpened stakes to the front. The story of the battle itself is quickly told. The attacking French cavalry and pedestrian men-at-arms, both so heavily armoured they had all the manoeuvrability of tortoises, got bogged down in the sucking mud. Henry then unleashed his secret weapon: the longbow of his English and Welsh archers, which was a paradigm-shift better than the French crossbow. A trained longbowman could shoot six aimed arrows a minute, arrows which could wound at 400 yards, kill at 200 and penetrate steel armour at 100.

GETTY IMAGES Henry V stoked the idea that the English were one nation, regardless of class