Hundred Years' War (1415–53)
The Lancastrian War was the third and final phase of the Anglo-French Hundred Years' War. It lasted from 1415, when King Henry V of England invaded Normandy, to 1453, when the English lost Bordeaux. It followed a long period of peace from the end of the Caroline War in 1389. The phase was named after the House of Lancaster, the ruling house of the Kingdom of England, to which Henry V belonged.
Dual monarchy of England and France
The English and French had been constantly at war over hereditary sovereignty in France; the Hundred Years' War (1337–1453) escalated, and the conflict between the two nations reached its peak in an intermittent series of belligerent phases, with each phase usually ending with a temporary truce lasting for a few years. In the first phase Edward III won some extraordinary victories against the French, most notably at Crécy and Sluys. His son Edward, the Black Prince also captured the French king John II at the battle of Poitiers in 1356, and routed the French army. The year 1360 marked the end of the first phase and an opportunity for peace.