It is likely that this composition is based on a lost painting or drawing by Leonardo da Vinci which Solario would have known from Leonardo’s prolonged stay in Milan working for the Ducal Court. The composition is a well known one as there is a signed version in the Metropolitan Museum of Art in New York.  The theme was a popular one in the Renaissance, and Solario himself used part of it in a single Head of Saint John the Baptist, in the Louvre, Paris, which is dated 1507, thus indicating a likely date for the larger composition here. The Louvre picture was even more popular than this one as numerous copies of it survive.

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