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
Prince of Wales York. Prior to his father inheriting the English throne in 1603, the future Charles I was created Duke of Albany and Earl of Ross in Scotland. Both Prince Frederick (eldest son of George II) and his son Prince George (later George III) were Duke of Edinburgh. The title Prince of Wales is given only to the heir apparent—somebody who cannot be displaced in the succession to the throne by any future birth. The succession had followed male-preference primogeniture, which meant that the heir apparent was the eldest son of the reigning monarch or, if he was deceased, "his" eldest son