Grand duchess in the context of Grand Duchy of Mecklenburg-Schwerin

A grand duchy is a country or territory whose official head of state or ruler is a monarch bearing the title of grand duke or grand duchess.

Prior to the early 1800s, the only Grand duchy in Europe was located in what is now Italy: Tuscany (declared in 1569). During the 19th century there were as many as 14 grand duchies in Europe at once, some of which were revived after the Napoleonic Empire. Some of these were sovereign and nominally independent (Baden, Hesse and by Rhine, Mecklenburg-Schwerin, Mecklenburg-Strelitz, Oldenburg, Saxe-Weimar-Eisenach and Tuscany), some sovereign but held in personal union with larger realms by a monarch whose grand-dukedom was borne as a subsidiary title (Finland, Luxembourg, Transylvania), some of which were client states of a more powerful realm (Cleves and Berg), and some whose territorial boundaries were nominal and the position purely titular (Frankfurt).