[Ryzorian]

Yea, I'd concur that it's a combination of culture and how much natural resources are available. Each group is good at certain things and not as good at others, it's covering each others weakness with their own strength, that makes the difference.

Sword arm, shield arm type thing, the shield blocks the sword attacks. While both can do the other, they aren't as effective doing what they weren't built to do. However, the complete soldier has both.

It's a simplistic I know, so don't over read it.