IMHO, this is a better way to implement the uniqueness of civ idea. If you have a lot of early wars, your civ tends to be better fighters. If you explorer a lot, they're intrepid. If you trade a lot, they'll be capitalist pigs

. And so on. It would make more sense then just saying that the Zulus are good at war even if they were isolated on some forsaken continent for the whole game.