The Battle of Agincourt, the day chivalry died. The day the greatest, most heavily armored and armed French knights were defeated by an army they outnumbered vastly, about 7,000 British troops against 15,000-25,000 French forces (again, including their best knights)... by a bunch of peasants carrying longbows, mallets, and wooden stakes.

Not only were the numbers lop-sided, but the British troop "diversity" was not good- about 5/6 of those 7,000ish men were archers, the remainder being dismounted men-at-arms. The French had quite a nice mixture of crossbows, men-at-arms, cavalry- a balanced force. On paper, with just this info, how could the British have possibly stood a chance?

Firstly, they had defender's advantage- so they prepped the battlefield. King Henry ordered all of his longbowmen to each chop down a tree, and fashion it into a stake that's about 5 feet long. The archers would lay these stakes out on the ground in front of them, launch volleys into a charging cavalry/infantry formation, and upon orders they would lift the stakes and pound them into the ground with a mallet. You've just turned your vulnerable line of ranged troops into men covered by an improvised pike wall.

The British were able to taunt the French Knights into making a foolish charge. The taunt? The bowmen would hold up their two bowstring fingers and start shouting, like "I'll kill you noble faggots with my two fingers, come and get it". The French nobility present on the battlefield were incensed at this rabble levy conducting themselves like this. And so they charged. They charged right into the ground that had been rained upon recently, and tilled by the British the day before, leaving it a muddy mess. This is where most of the fighting would occur.

It's pretty horrifying- stories about men drowning in the mud and shit. Witnesses said the British men-at-arms would drag the heavily armored French to the ground, and 3-on-1 they would fucking drown the poor bastard in 2 inches of mud/blood/guts. The longbowmen (positioned in the treeline on high ground on either side of where the men-at-arms were engaging) eventually ran out of arrows... so Henry told them to drop their bows, and charge. The archers grabbed whatever melee weapons they had (lots of axes, maces, but a lot of them ended up using their mallets) and charged into the bloody mess. The French were butchered almost to-a-man.

The historical significance of this battle can't be understated- it actually revolutionized the way military service in Europe took shape. No longer was it levies being called up by their local lord, fighting because if they did not fight, they'd be hanged for treason- now the men would be paid a good wage to go on campaigns! See, these longbowmen at Agincourt were among the first to recieve this kind of treatment from the nobility, and it is theorized that they probably would not have been willing to face such odds without being treated well by young King Henry, and they were being paid- so while they were running around in France, they were happy that their families back home had some measure of security because they were being paid. This led to much higher morale, probably contributed majorly to victory.

Check out the battle of Agincourt, famous for movable anti-cavalry-charge stakes and more.