I have collected many period photos, both military and civilian, and one interesting clue as to place and date, is his waxed upturned mustache. This style was popular among the European monarchies in a variety of changing lengths and forms from the mid 19th and early 20th Century. And became a fashion trend among their subjects, especially those men who served in the Armed forces, who would compliment their appearance with the 'King's Mustache'. It was popular in WW1. The style progressed into the very short sharp pointed version you have in your photo, that was popular among German and Austrian-Hungarian troops of the Great War.
Here is a photo of Italy's Vittorio-Emmanuele II (ca. 1860) with his:
Here is a photo of Wilhelm II of Germany with his:
Famous Italian WW1 soldier and poet, Gabriele d'Annunzio with his:
Italian officer WW1 with his:
And here is a photo of my grandfather who fought in WW1 in the Italian Infantry with his:
This short sharp waxed upturned pointed style mustache in your photo seems to be a purely European thing during that period of the Great War (especially among German/Austrian & Northern Italians), and not popular among American men.
So, taking the above information, combined with the photo evidence, I can safely come to but one conclusion: I need a life!
