The Battle of Val-ès-Dunes was fought in 1047 by the combined forces of William, Duke of Normandy and King Henry I of France against the forces of several rebel Norman barons, led by Guy of Brionne, the son of Reginald I, Count of Burgundy. As a result of winning the battle, William (later William the Conqueror) was able to retain his title and maintain control over the western half of his duchy.