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 the Black Prince steel". Richard Barber suggests that the name's origins may have lain in pageantry, in that a tradition may have grown up in the 15th century of representing the prince in black armour. He points out that several chronicles refer to him as Edward the IV (the title he would have taken as King had he outlived his father): this name would obviously have become confusing when the actual Edward IV succeeded in 1461, and this may have been the period when an alternative had to be found. Edward's reputation for brutality in France is also well documented, and it is