Henry I of France whose death Henry was left to deal with his rebel sibling. In 1032, he placated his brother by giving him the duchy of Burgundy which his father had given him in 1016. In an early strategic move, Henry came to the rescue of his very young nephew-in-law, the newly appointed Duke William of Normandy (who would go on to become William the Conqueror), to suppress a revolt by William's vassals. In 1047, Henry secured the dukedom for William in their decisive victory over the vassals at the Battle of Val-ès-Dunes near Caen; however, Henry would later support the barons against
Hoël II, Duke of Brittany in the east and the House of Cornouaille in the west may have further strengthened Brittany at a time when external interference was attempted by William the Conqueror. After Hawise's death in 1072, Hoël acted as regent for his son, Alan IV, until the latter reached his majority in 1084. During his reign he faced several rebellions from Breton nobles. Geoffrey Grenonat of Rennes (a natural son of Duke Alan III of Brittany and thus a half-brother of Hawise) led a revolt and was joined by Ralph de Gael who had returned to Brittany from England after the failure of