 Edmund of Langley, 1st Duke of York, 1st Earl of Cambridge, KG (5 June 1341 – 1 August 1402) was a younger son of King Edward III of England and Philippa of Hainault, the fourth of their five sons who lived to adulthood.He was the founder of the House of York, but it was through the marriage of his younger son, Richard of Conisburgh to Anne Mortimer that the Yorkist faction in the Wars of the Roses made its claim on the throne.The other party in the Wars of the Roses, the Lancasters, were descendants of Edmund's elder brother, John of Gaunt whose son Henry usurped the throne of Richard II in 1399.