Archduke

Archduke (Latin: Archidux; German: Erzherzog), or in feminine form Archduchess (Latin: Archiducissa; German: Erzherzogin) was a title of nobility in the Holy Roman Empire, and later in the Austrian Empire and the Austro-Hungarian Monarchy. It denoted a rank above the duke, but below the king or emperor, and was roughly equal to that of a grand duke. The title was initially devised by Rudolf IV, Duke of Austria (d. 1365) from the House of Habsburg, who claimed the archducal rank and title since 1358-1359, and the same aspiration was later reaffirmed by Ernest, Duke of Austria (d. 1424), but both failed to secure imperial confirmation of their claims. The title was officially established by Emperor Frederick III in 1453, who awarded the archducal title to the Austrian ruling House of Habsbur...