These two medallions were in the Hohenzollern-Sigmaringen collection in the nineteenth century, and Heinrich Thyssen-Bornemisza acquired them sometime before 1938. The bust in profile on the left portrays Emperor Charles V (1500–1558), and its counterpart on the right is supposedly Isabella of Portugal (1503–1539), although the image does not resemble any known likenesses of her. The physical features of both subjects are harsh and exaggerated: the king’s nose is excessively long and his chin juts out too far, and Isabella’s revealing neckline is inappropriate for someone of her elevated rank. 

Both pieces have perforated surfaces, indicating that they may have been part of a piece of furniture or decorative panelling in a Kunstkammer or Wunderkammer-type room.