The only thing I can add is to be careful. I have male friends from other cultures but a relationship is totally different. Think first if you are willing to share a man with another woman. In his culture it may be ok but maybe it's not ok for you. Wouldn't be for me.
I don't know where the guy is from but I am guessing middle east somewhere going by the info about multiple wives. Men can take a woman of different belief because in thier culture the man is ultimately head of the household and therefore the woman can change religious beliefs. If an Islamic woman takes a man from another religion they can be killed. It happened in Sweden last year. A girl was killed by her father because her relationship with a Swede was a dishonor to the religion and thus to him. There were alot of people at my school who believed it was ok for the father to do that. I only tell you this so you are aware of the seriousness of culture mixing in a relationship. I have no idea what kind of man he is or of his religious beliefs. Just be careful.
Also I recently asked a woman from Iraq about multiple wives. She said it is not common anymore and mainly rich men or men who have a strong need for more than one woman do it. It isn't usual but possible. Many now choose one wife. If you do take on more than one you are responible for thier care so mostly the rich men can do it.
Probably should've minded my own business but there's what I know.
Heidu