Sebastiano Ricci and Leopoldo dal Pozzo, The Doge and Signoria Pay Homage to the Relics of St. Mark
West façade, St. Mark's Basilica, Venice
Presumably the Doge is the one in the light gray hood and cape, though his ducal cap does not look quite like those seen in other images of the Doges. The turbaned man on the throne at the far left should be the Caliph known to the translation legend as "Regulus," whose raids on the church where St. Mark had lain inspired Venetian merchants to "save" the body (Acta Sanctorum, April vol. 3, 353-55).
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Photographed at the site by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.
Identification of the subject, artists, and date: Vio, 62.