St. Theodore Stratelates
St. Marks Square, Venice
A website describing the square says this was set up as St. Theodore, not St. George. However, most of the statue is in fact "an early St. George" and the head is that of a Roman emperor. Theodore also slays a dragon on p. 46 of Weitzmann, The Icon.
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Photographed in St. Marks Square by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.