Duke of Normandy as the reign of William II (1035–87), the ruler of Normandy could style himself "prince and duke, count of Normandy" as if unsure what his title should be. The literal Latin equivalent of "Duke of Normandy", "dux Normanniae", was in use by 1066, but it did not supplant "dux Normannorum" until the Angevin period (1144–1204), at a time when Norman identity was fading. Richard I experimented with the title "marquis" ("marchio") as early as 966, when it was also used in a diploma of King Lothair. Richard II occasionally used it, but he seems to have preferred the title duke.
William II, Duke of Aquitaine William II, Duke of Aquitaine William II the Young (died 12 December 926) was the Count of Auvergne and Duke of Aquitaine from 918 to his death, succeeding his uncle William I. William was son of the Acfred I of Carcassonne and Adelinde, William I's sister and Bernard Plantapilosa's daughter. Immediately after succeeding his uncle, he made war on the Burgundians and Normans, who refused to accept Rudolph as king of France. His support of the king, however, was insincere. He later revolted and Rudolph led an army into Aquitaine, but was called back to defend the Rhine from the