Like I tried to explain, the "Unknown God" and their temples were much similar to the Tomb of the Unknown Soldier, it's not a particular person in general, but refers to the possibility of another, so the Unknown God can be several different Gods who have remained secret for some reason, but were worshiped for posterity. I just plan to use the concept to create such a God ^^ Of a nature I have not yet decided .-. 

I'd imagine I'll use the concept to emulate the "Something is out there" God that people look to, that hell, I look to. I just see it as an interesting opportunity to give a fictional face to something :P