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.
History of Hertfordshire
Hertford Castle was used as a gaol for a series of important captives during the Hundred Years' War. This was actually a series of separate wars that lasted a total of 116 years, between 1337 and 1453. The Plantagenet Kings of England fought the Valois Kings of France, almost entirely on French soil. Queen Isabella was imprisoned by her son, the King, in Hertford Castle in 1330, as were King David II of Scotland and his queen in 1346, after the Battle of Neville's Cross. King John II of France was imprisoned there in 1359 in considerable luxury.