Monarchy of Luxembourg in the context of "Grand Duke"

Grand duke (feminine: grand duchess) is a European hereditary title, used either by certain monarchs or by members of certain monarchs' families. The title is used in some current and former independent monarchies in Europe, particularly:

• in present-day Luxembourg, the last surviving Grand Duchy
• historically by the sovereigns of former independent countries, such as Tuscany (from 1569 to 1860, now part of Italy)
• in Baden, Hesse, Oldenburg, Mecklenburg-Schwerin, Mecklenburg-Strelitz and Saxe-Weimar-Eisenach (officially simply the Grand Duchy of Saxony) – grand duchies from 1815 to 1918, and all now part of Germany
• formerly also in some countries in Northern Europe, such as the Grand Duchy of Finland or the Grand Duchy of Lithuania
• currently by claimants to the Russian Imperial Throne (eg. Grand Duke George Mikhailovich of Russia)

Nassau Castle, located in Nassau, Rhineland-Palatinate, Germany and named after it, was a castle and the ancestrial seat of the House of Nassau and also its namesake, also it is the namesake of the historical Nassau realms of the County and Duchy of Nassau . The ruins of the castle are situated on a rock outcropping about 120 m (390 ft) above the Lahn River. The House of Nassau was an aristocratic dynasty among whose descendants are the present-day monarchy of the Netherlands and Luxembourg.