religion and nationality has othing to do in this case, as any Muslim can legally marry a christian girl. But if you both are sincere to each other. The other main aspect is the traditions and culture. If the guy is from such a culture that he may need you to be restricted and not to mix with other guys etc etc....then you have to think first. As per my knowledge, it is very difficult for the girls of some nationalities to adjust in such conditions as they need full freedom and most of Muslim cultures will now allow them to roam around freely as they wish. But still I have seen some christian girls from various nationalities, who married Muslim guys and they are very happy because they really love their husband and follow their rules. If you are ready for that then go ahead....