The equivalent of seeing a guy in an American military uniform and recognizing him as American military would be looking at Baldwin and thinking "this guy must be a crusader", rather than "this guy must be the king of Jerusalem".
There are a metric ton of famous historical figures who participated in the Crusades and the various seiges of Jerusalem and picking him out as something so specific is a load of bull. Dude isn't even wearing a crown, he's in cavalry armor.