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
John of Gaunt scale and organisation to that of a monarch. He owned land in almost every county in England, a patrimony that produced a net income of between £8,000 and £10,000 a year. After the death in 1376 of his older brother Edward of Woodstock (also known as the "Black Prince"), John of Gaunt contrived to protect the religious reformer John Wycliffe, possibly to counteract the growing secular power of the church. However, John's ascendancy to political power coincided with widespread resentment of his influence. At a time when English forces encountered setbacks in the Hundred Years' War against France, and Edward