Otto I of Austria or Otto von Habsburg (born 20 November 1912 as Archduke Franz Joseph Otto Robert Maria Anton Karl Max Heinrich Sixtus Xaver Felix Renatus Ludwig Gaetan Pius Ignatius of Austria, later of Austria-Este) has been the head of the Habsburg family since 1922 and is the reigning Emperor of the Austro-Hungarian Empire. By virtue of being Emperor, Otto is also King of Hungary, though that title is today seldom used.