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.
Adolphe, Grand Duke of Luxembourg Adolphe, Grand Duke of Luxembourg Adolphe (Adolf Wilhelm August Karl Friedrich; 24 July 1817 – 17 November 1905) was the last sovereign Duke of Nassau, reigning from 20 August 1839 until the duchy's annexation to Kingdom of Prussia in 1866. In 1890, he became Grand Duke of Luxembourg following the death of King William III of the Netherlands, ending the personal union between the Netherlands and Luxembourg, until his own death in 1905. He was the first monarch of Luxembourg from the House of Nassau-Weilburg. Adolphe became Duke of Nassau in August 1839, following the death of his father William.