I haven't read all the replies so correct me if i'm wrong, but according to what ive picked up, from books in all:
The mandalorians are a nomadic group. They do not care about race/species, just culture. They are experts in the art of hunting, and fighting, and also close combat using the beskad. They mine, because mandalorian metal is strong, and they market what products they make out of that metal. In the off seasons, a lot of mandalorians are smithies and farmers [except boba fett of course] and because they dont believe in bloodlines, they tend to adopt a lot of kids, and train them to fight-- you're not a real man untli you train. They are cold blooded fighters when they need to survive, but loving and caring at home [again, except boba fett]
I'd kind of disagree on the spartans part because they remind me more of the maori. Maybe because the two distinctive faces of the two most famous mandalorians-- jango and boba fett were played by maoris, but when the europeans [pakehas] started settling on new zealand, some were sort of "adopted" by the tribes and trained as warriors, some also earned the right to be tattooed. The mandalorians are more ihgh tech of course, but new zealand was a land that was discovered by the maori, and if ou look up some maori weapons, a lot of them resemble the beskad. The women of the maori are elite too.