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 medieval England extending principally over the counties of Cheshire and Flintshire. A Prince of Wales also holds a number of additional titles. As heir apparent to the English/British throne he is—if the eldest living son of the monarch—Duke of Cornwall. As heir apparent to the Scottish throne he is Duke of Rothesay, Earl of Carrick, Baron of Renfrew, Lord of the Isles, and Prince and Great Steward of Scotland. Individual princes have also held additional titles, which were theirs prior to becoming Prince of Wales. Before ascending the throne Henry VIII, Charles I and George V were each Duke of