Robert Curthose asking his father's pardon. Robert Curthose, c.?1054 1134, aka Robert II or Robert III. Son of William the Conqueror. Duke of Normandy from 1087 until 1106 and unsuccessful claimant to the English throne. During a battle in January 1079 Robert unhorsed King William, his father, in combat and succeeded in wounding him, stopping his attack only when he recognized his father's voice. From Cassell's History of England, published c.1901