Edward III is noted for his military success and for restoring royal authority after the disastrous and unorthodox reign of his father, Edward II. Edward III transformed the Kingdom of England into one of the most formidable military powers in Europe. His 50-year reign was the second-longest in medieval English history, and saw vital developments in legislation and government, in particular the evolution of the English Parliament, as well as the ravages of the Black Death. He outlived his eldest son, Edward the Black Prince, and the throne passed to his grandson, Richard II.

He declared himself rightful heir to the French throne in 1337. This started what became known as the Hundred Years' War. Following some initial setbacks, this first phase of the war went exceptionally well for England; victories at Crécy and Poitiers led to the highly favourable Treaty of Brétigny, in which England made territorial gains, and Edward renounced his claim to the French throne.  (Wikipedia article).