Other Dynastic Habsburg Use
Often imprecisely rendered as Grand Duke (actually a different rank with which it should not be confused), Grand Prince (in German Großfürst) was used for the rulers of Lithuania (which in 1386 formed a personal union with the elective kingdom Poland) and Moscovia, the nucleus of later imperial Russia, until its ruler assumed the sovereign style Tsar of royal rank, and still later emperor in imperial Russia. "Archduke" was used for non-sovereign rulers as a titular rank for princes of the Austrian ruling house of Habsburg, in titulary chief of an Austrian homeland, but without becoming its hereditary ruler since all territories remained vested in the Austrian crown. Occasionally it might be combined with a separate gubernatorial mandate.
From the 16th century onward, Archduke and its female form, Archduchess, came to be used by all the members of the 'Royal and Imperial' House of Habsburg, similar to the title Prince (of the blood) in many other royal houses. For example, Queen Marie Antoinette of France was born Archduchess Maria Antonia of Austria. After the dissolution of the Holy Roman Empire this practice was maintained in the Austrian Empire (1804–1867) and the Austro-Hungarian Empire (1867–1918).
The official use of Austrian aristocratic titles such as archduke has been illegal in the Republic of Austria for Austrian citizens since the Law on the Abolition of Nobility (Gesetz vom 3. April 1919 über die Aufhebung des Adels, der weltlichen Ritter- und Damenorden und gewisser Titel und Würden). Thus, those members of the extended Habsburg family who are citizens of the Republic of Austria, are simply known by their respective first name and their surname, Habsburg-Lothringen. However, members of the family who are citizens of other countries such as Germany, where aristocratic titles have become part of the name, may use the title. Otto Habsburg-Lothringen (1912–2011) was an Austrian, Hungarian and German citizen. As he lived in Germany, he was known as Otto von Habsburg.
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