He is wearing some sort of Masonic uniform, probably of a Masonic "Knights Templar" group. An example of William McKinley (a president of the U.S.) wearing a very similar uniform is at http://www.mastermason.com/sttm-emag/sep09.htm#mck . It is implied that the McKinley Museum's exhibit stated that it was a Knights Templar uniform. There are several organizations based on that name that are members of Freemasonry -- note: they are not actually descended of the original Knights Templar. I can also find a photograph of one Albert Sumner Bradford from the Online Archive of California here , again of a very similar uniform but there identified only as "Masonic". A brief biography of Frederick Mills Valz states that his father, A. M. Valz of Staunton, Virginia (the city where your image originated), was in the Masons and the Elks.