Duke of Aosta

In the mid-13th century the Hohenstaufen Holy Roman Emperor Frederick II made the County of Aosta a duchy; its arms were carried in the Savoyard coat of arms until the unification of Italy in 1870. The region remained part of Savoy lands, with the exception of a French occupation, 1539—1563. The title Duke of Aosta was given to various princes of the dynasty of Sardinia, second sons of the reigning monarch. It can be compared to the English Duke of York, French Duke of Orléans, Swedish Duke of Södermanland and the Scottish Duke of Albany. It remained in the branch of Prince Amedeo of Savoia, the second son of king Victor Emanuel II of Italy, as he was the first ever cadet prince Duke of Aosta who left male heirs. The subsidiary titles of the Duke of Aosta are, from the heritage of Maria Vittoria dal Pozzo, the mother of Duke Emanuele Filiberto, Prince della Cisterna and of Belriguardo, Marquess of Voghera, and Count of Ponderano. Ponderano was created in 1559, Voghera in 1618; Cisterna and Belriguardo as princely in 1670. The title has been used since July 2006 by Amedeo's son Prince Aimone, Duke of Apulia (born 1967), who is married to Princess Olga of Greece, younger daughter of Prince Michael of Greece and Denmark.