A human barbarian's ethnicity must either be Rjuven or Vos. Rjuvik is located far outside of the center of action for this campaign and Vos barbarians largely worship evil gods,. PCs are, of course, remarkable characters who quite often are the exception to the rule. If you wish to play a barbarian character, he or she will need to be Rjuven or Vos and you should create a backstory that explains either why your character is so far from home (Rjuvik) or how your character came to reject the evil gods of his or her people.