1. Number
The size of the medieval armies that participated in one or another battle is quite problematic to find out. This is due to the lack of accurate documents. Despite this, it can be clearly said that the British were clearly outnumbered at the Battle of Agincourt.
The English army at Agincourt consisted of approximately 900 men at arms and 5,000 archers - a total of 6,000 armed men.
The French had about 25,000 soldiers.
The very numerical superiority gave the French a huge advantage.
2. Heavily armed knights
The battlefields of that period were dominated by knights - a powerful professional military force. The traditional military elite of the feudal society. From childhood they were accustomed to the art of war.
Many of them were experienced soldiers - French knights with weapons in their hands fought with the British for almost a century, and also participated in conflicts between large and small feudal lords in the territory of the French kingdom.
Richer than the common foot soldiers, the knights were well equipped for battle.
In particular, they wore heavy armor, which increasingly consisted of full plates. Even arrows from bows were rarely able to penetrate this armor (except at close range), allowing its wearers to safely rush into battle.
According to the military logic of the time, the French troops outnumbered them both in quality and in numbers.
3. Diseases
The English army arrived from Harfleur, where it spent over a month besieging the city.
Camping in a swampy area, many of the warriors fell ill.
About 2,000 people died of dysentery even before they took Harfleur.
That contributed to the numerical weakening of the English army, which then marched to Calais.
Many were still ill by the time they encountered the French.
4. Hunger
When the British left Harfleur on October 6, they took with them supplies for eight days, leaving behind their baggage train for a quick march.
They plundered farms and countryside as they passed.
But the pressure of the French persecution kept them moving incessantly. And by the time of the battle, the British had no food left.
5. Exhaustion
The trek from Harfleur was grueling.
Upon reaching the Seine, the path of the English army was blocked by the French, who did not allow it to cross the river.
Then another French army began to pursue them the rest of the way, not giving them rest.
The march grew longer and longer.
And because of the pouring rain, the unpaved roads along which the British were moving were turned into mud, which only complicated the movement of the army.
6. French caution
The French were usually not very careful at Agincourt, where they ruthlessly threw themselves under a hail of English arrows.
But they exercised strategic caution in preparing for battle.
Instead of rushing directly at Henry and his army, the French commanders tried to block his advance.
By destroying river crossings and obstructing the advance of the British, they forced the enemy to approach them, giving themselves more time to prepare.
On October 24, they finally decided it was time to fight, defeat Henry's army and stop him from fleeing France.
They entered the Calais road ahead of the British, stopping them halfway.
Late in the evening of the same day, Henry ordered his troops to take up defensive positions on the ridge that crossed the road. They did not have the slightest chance of attacking the French head-on. But if they could fight on favorable terms, they would at least survive.
The French soldiers were very tempted to attack the British immediately. But they learned to exercise some caution after their previous clashes with the British at Crécy and Poitiers.
Why did the French lose?
Looking back, we see that the French feudal lords clung to outdated ways of waging war.
Tactical superiority in attacks by heavily armed warriors has been declining for over a century.
Infantry defensive tactics using spears and bows now brought victories across the continent. Last but not least, in similar battles at Crécy and Poitiers at the beginning of the Hundred Years War.
The advantages of this infantry tactic were invaluable, thanks to the truly decisive factor in battle - leadership.
The French feudal lords were disorganized and divided.
Two landowner factions fought for power in the country. And their adherents tried their best to work together.
The British, on the other hand, had one common and chief feudal lord, Henry.
