Robert II of Normandy, or Robert Curthose, was the eldest son of William the Conqueror and succeeded his father as Duke of Normandy in 1087, reigning until 1106. Robert was also an unsuccessful claimant to the throne of the Kingdom of England. The epithet "Curthose" had its origins in the Norman French word courtheuse 'short stockings' and was apparently derived from a nickname given to Robert by his father; the chroniclers William of Malmesbury and Orderic Vitalis reported that William the Conqueror had derisively called Robert brevis-ocrea.

William the Conqueror, sometimes called William the Bastard, was the first Norman king of England, reigning from 1066 until his death. A descendant of Rollo, he was Duke of Normandy from 1035 onward. By 1060, following a long struggle to establish his throne, his hold on Normandy was secure. In 1066, following the death of Edward the Confessor, William invaded England, leading an army of Normans to victory over the Anglo-Saxon forces of Harold Godwinson at the Battle of Hastings, and suppressed subsequent English revolts in what has become known as the Norman Conquest. The rest of his life was marked by struggles to consolidate his hold over England and his continental lands, and by difficulties with his eldest son, Robert Curthose.