The Hundred Years' War — Agincourt

The Hundred Years' War is somewhat of a misnomer. The "war" was actually a series of conflicts waged over a period of 116 years (1337-1453) between the kingdoms of France and England. The Battle of Agincourt, fought on October 25, 1415 was a major battle of the protracted war.

King Henry V led a small army of less than 10,000 troops against a much larger French army estimated between 12,000 and 36,000! Henry invaded northern France after negations failed, claiming the title of King of France through Edward III, his great-grandfather. The battle of Agincourt took place after Henry had captured the port city of Harfleur.

French king Charles IV was not in command of the French Army as he was ill and not in a proper state of mind. In his place was the Constable of France, Charles d'Albret. In reality powerful French nobles did whatever they desired, leading to a compromised battle plan.
The battle was fought on a narrow strip of land between two woods. The majority of Henry's troops were armed with the latest in battlefield technology — the long bow. Lining up in front of the British men-at-arms, the longbowmen exacted a heavy toll on a disorganized French cavalry charges. 

The Constable led the main French assault of dismounted men-at-arms. Wearing heavy armor, the troops slowly crossed the muddy field (which had been churned up by the cavalry charge) under a hail of arrows. Those who reached the English line managed to push back the archers. However, the unencumbered archers were able to more easily navigate the muddy terrain. Using hatchets and swords, the then-exhausted French were easily repulsed with great loss of life.

By the most conservative estimate the French lost six times as many men as the English, including their leader, Charles d'Albret. Henry was soon compelled to return to England but the victory bought him time to prepare for a new campaign. Henry was eventually recognized as the heir to the French throne, bonding the claim with his marriage to Catherine of Valois, daughter of Charles VI.