Duchy of Cornwall from Duchy income, assisted by Grants-in-aid from the Queen. If there is no duke (for example, if the monarch does not have any male children) the duchy income reverts to the monarch and the annual Sovereign Grant is reduced annually by the amount of the duchy's income. The duchy was established on 17 March 1337 by the Royal Great Charter out of the former Earldom of Cornwall by Edward III for his son, Edward, Prince of Wales, the "Black Prince", who became the first Duke of Cornwall. The charter established that the Duke of Cornwall is to be the eldest
Edward III of England Edington and Chief Justice William de Shareshull. It was not until the mid-1350s that military operations on the Continent were resumed on a large scale. In 1356, Edward's eldest son, Edward, the Black Prince, won an important victory in the Battle of Poitiers. The greatly outnumbered English forces not only routed the French, but captured the French king, John II and his youngest son, Philip. After a succession of victories, the English held great possessions in France, the French king was in English custody, and the French central government had almost totally collapsed. There has been a historical debate as