The Anglo-French wars of 1337–1453: Crécy, Poitiers, Agincourt, Joan of Arc, and the artillery that ended it.
The Hundred Years' War lasted a hundred and sixteen years, was not continuous, and was not really about the English claim to the French throne that provided its pretext. It was a succession of campaigns, truces and civil wars between two crowns whose lands and loyalties had been entangled since 1066.
Militarily it is the period in which the balance between armoured cavalry and missile infantry shifted decisively, and then shifted again. Crécy, Poitiers and Agincourt are three variations on the same lesson — dismounted men-at-arms and massed longbowmen on chosen ground, against a numerically superior force that had to come to them. The English won every one of those battles and still lost the war.
What reversed it was partly Joan of Arc, whose eighteen months transformed a collapsing French position at Orléans, and partly something less romantic: the French crown built a professional standing army and the best artillery train in Europe. Formigny and Castillon were decided by guns, and Castillon in 1453 is where the medieval military age is usually said to end.
The archive covers the battles, the commanders on both sides, and the weapons and armour that made the period what it was.