Is he just a giant Nord? I know hes pretty old .... and once lived and died ... If this is the case, were all Nords at that time that tall? Lore nazis please correct if im wrong, if i knew i wouldnt be asking.

http://www.uesp.net/wiki/Skyrim:Tsun

He's a god.

Most likely never a mortal(at least, that's how I remember it), so race is irrelevant.

Dead Et'ada aligned with man and Shor, so he appears Nordic/Atmoran.

Tsun is Z'en is Zeht, is Zenithar. You talked to the aspect of a god.