Edward III was one of the most successful English monarchs of the Middle Ages. He remained on the throne for 50 years; no English monarch had reigned for as long as Edward since Henry III, and none would until George III. Having restored royal authority after the disastrous reign of his father, Edward II, he went on to transform the Kingdom of England into the most efficient military power in Europe.

Edward was crowned at the age of fourteen, following the deposition of his father. When seventeen years old he led a coup against his regent, Roger Mortimer, and began his personal reign. After defeating, but not subjugating, the Kingdom of Scotland, he declared himself rightful heir to the French throne in 1337, starting what would be known as the Hundred Years' War. Following some initial setbacks, the war went exceptionally well for England; the victories of Crécy and Poitiers led up to the highly favourable Treaty of Brétigny. Edward’s later years, however, were marked by international failure and domestic strife, largely as a result of his inertia and eventual bad health.

Edward was also responsible for establishing the Order of the Garter, and his reign saw vital developments in legislature and government — in particular the evolution of the English parliament. By character he was a temperamental man, but also capable of great clemency. He was, in most ways, a conventional king, and his interests lay mainly in the field of warfare. He was highly revered in his own time and for centuries after.