The Latin title
archidux is first attested in reference to
Bruno the Great, who ruled simultaneously as
Archbishop of Cologne and
Duke of Lotharingia in the 10th century, in the work of his biographer
Ruotger of Cologne. In Ruotger, the title served as an honorific denoting Bruno's unusual position rather than a formal office. The title was not used systematically until the 14th century, when the title "Archduke of Austria" was invented in the forged
Privilegium Maius (1358–1359) by Duke
Rudolf IV of Austria, called Rudolf the Founder (German: Rudolf der Stifter). Rudolf originally claimed the title in the form
palatinus archidux ("palatine archduke"). The title was intended to emphasize the claimed precedence (thus "Arch-") of the
Duchy of Austria, in an effort to put the Habsburgs on an even level with the
Prince-Electors of the Holy Roman Empire, as Austria had been passed over when the
Golden Bull of 1356 assigned that dignity to the four highest-ranking secular
Imperial princes and three Archbishops.
Holy Roman Emperor Charles IV refused to recognise the title, as did all the other ruling dynasties of the member countries of the Empire. But Duke
Ernest the Iron and his descendants unilaterally assumed the title of
Archduke. The archducal title was only officially recognized in 1453 by
Emperor Frederick III, when the Habsburgs had solidified their grip on the throne of the
de jure elected
Holy Roman Emperor, making it
de facto hereditary. Despite that imperial authorization of the title, which showed a Holy Roman Emperor from the Habsburg dynasty deciding over a title claim of the Habsburg dynasty, many ruling dynasties of the countries which formed the Empire refused to recognize the title "Archduke".
Ladislaus the Posthumous, Duke of Austria, who died in 1457, never got in his lifetime the imperial authorization to use it, and accordingly, neither he nor anyone in his branch of the dynasty ever used the title. Emperor Frederick III himself simply used the title "Duke of Austria", never
Archduke, until his death in 1493. The title was first granted to Frederick's younger brother,
Albert VI of Austria (d. 1463), who used it at least from 1458. In 1477, Frederick III also granted the title of
Archduke to his first cousin,
Sigismund of Austria, ruler of
Further Austria (). Frederick's son and heir, the future
Emperor Maximilian I, started to use the title, but apparently only after the death of his wife
Mary of Burgundy (d. 1482), as
Archduke never appears in documents issued jointly by Maximilian and Mary as rulers in the
Low Countries (where Maximilian is still titled "Duke of Austria"). The title appears first in documents issued under the joint rule of Maximilian and his son
Philip in the Low Countries.
Archduke was initially borne by those dynasts who ruled a
Habsburg territory—i.e., only by males and their consorts,
appanages being commonly distributed to
cadets. But these "junior"
archdukes did not thereby become sovereign hereditary rulers, since all territories remained vested in the Austrian crown. Occasionally a territory might be combined with a separate gubernatorial mandate ruled by an archducal cadet. ==Usage==