Richard of York, 3rd Duke of York (21 September 1411 – 30 December 1460), was a leading English magnate, a great-grandson of King Edward III through his father and a great-great-great-grandson of that king through his mother. He inherited great estates, and served in various offices of state in France at the end of the Hundred Years' War, and in England, ultimately governing the country as Lord Protector during Henry VI's madness. His conflicts with Henry's wife, Margaret of Anjou, and other members of Henry's court, as well as his competing claim on the throne, were a leading factor in the political upheaval of mid-fifteenth-century England, and a major cause of the Wars of the Roses. Richard eventually attempted to take the throne but was dissuaded, although it was agreed that he would become King on Henry's death (being Lord Protector and Prince of Wales in the meantime.) Within a few weeks of securing this agreement, he died in battle.
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