Quote Originally Posted by Chemical View Post

That's his race (both him and Cecil)

If you recall their father was lunarian and their mother was human.

But yeah, my educated guess would be that he is a Dark Knight.
I think it would make good game play sense to have it so that he was a Dark Knight while his brother is a Paladin. The whole Ying and Yang - Balance - Good vs Bad - Brother thing.
That's what I think as well. It makes me wonder how long Golbez had his henchman impersonating the King of Baron? The game or the manual mentioned that Cecil became a Dark Knight at the King's request.