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, Duke of Austria Austrian duchies, and Frederick IV, the youngest, Tyrol and Further Austria. William, Duke of Austria William ( – 15 July 1406), known as William the Courteous (), a member of the House of Habsburg, was Duke of Austria from 1386. As head of the Leopoldian line, he ruled over the Inner Austrian duchies of Carinthia, Styria and Carniola as well as the County of Tyrol and Further Austria from 1396 until his death. Born in Vienna, William was the oldest son of Duke Leopold III of Austria (1351–1386) and his consort Viridis Visconti (1352–1414), a daughter of Lord Bernabò of