Edward of Langley, 2nd Duke of York, 2nd Earl of Cambridge, Earl of Rutland, Earl of Cork, Duke of Aumale, KG (c.1373 – 25 October 1415), was the eldest son of Edmund of Langley, 1st Duke of York, by his first wife Isabella of Castile, and the grandson of King Edward III. He held significant appointments during the reigns of three monarchs Richard II, Henry IV, and Henry V, and was slain at the Battle of Agincourt in 1415. He translated a hunting treatise, The Master of Game.
The will can be read here (in Anglo-Norman).