Focus on this artwork and explore the Provenance.
The armor was acquired by the German collector Franz, Count of Erbach-Erbach in the 19th century (a non-original burgonet helmet was added about this time) and was then thought to be that of Albert V, Duke of Bavaria (the son-in-law of Ferdinand), kept by Franz and his heirs at Erbach Castle, and is currently in the collection of the Metropolitan Museum of Art.The identification with Ferdinand I was first made by the director of the armory at the Kunsthistorisches Museum, on the basis of the wearer's slight build and relatively short height (no more than  5'7" or 170 cm), straight back, slim waist and long arms, the similarity to his other documented armors, and importantly the Reichsadler eagle on the sabatons. When the identification was initially made with Albert V, it had been assumed it was made for him as a young man, as he gained weight in later life.  Albert was also a member of the Order of the Golden Fleece, and the imperial insignia could be seen as representing his marriage to Ferdinand's daughter.
Ferdinand I sabaton Reichsadler burgonet Erbach Castle Franz, Count of Erbach-Erbach Albert V, Duke of Bavaria Kunsthistorisches Museum Metropolitan Museum of Art