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.
Richard of York, 3rd Duke of York
As York reached majority, events were unfolding in France which would tie him to the events of the ongoing Hundred Years' War. In the spring of 1434, York attended a great council meeting at Westminster which attempted to conciliate the king's uncles, the dukes of Bedford and Gloucester (heads of the regency government), over disagreements regarding the conduct of the war in France. Henry V's conquests in France could not be sustained forever, as England either needed to conquer more territory to ensure permanent French subordination, or to concede territory to gain a negotiated settlement. During Henry VI's minority, his Council took advantage of French weakness and the alliance with Burgundy to increase England's possessions, but following the Treaty of Arras of 1435, Burgundy ceased to recognise the English king's claim to the French throne.