Edmund of Langley, 1st Duke of York, KG (June 5, 1341 – August 1, 1402) is the fourth surviving son of King Edward III of England and Philippa of Hainault.

Like many medieval English princes, Edmund gains his nickname from his birthplace of Kings Langley Palace in Hertfordshire.

He is the founder of the House of York, but it is through the marriage of his younger son, Richard of Conisburgh, 3rd Earl of Cambridge, to Anne de Mortimer, great-granddaughter of Edmund's elder brother Lionel, that the Yorkist faction in the Wars of the Roses makes its claim on the throne (the other party in the Wars of the Roses, the incumbent Lancasters, being the male descendants of his elder brother John of Gaunt, Edward III's third son).