Context: The origins of the szlachta, while ancient, have always been considered obscure.:207 As a result, its members often referred to it as odwieczna (perennial).:207 Two popular historic theories of origin forwarded by its members and earlier historians and chroniclers involved descent from the ancient Iranian tribes known as Sarmatians or from Japheth, one of Noah's sons (by contrast, the peasantry were said to be the offspring of another son of Noah, Ham—and hence subject to bondage under the Curse of Ham—and the Jews as the offspring of Shem). Other fanciful theories included its foundation by Julius Caesar, Alexander the Great:207 or regional leaders who had not mixed their bloodlines with those of 'slaves, prisoners, and aliens'.:208

Question: What was important and unique about regional leaders?

Answer: had not mixed their bloodlines with those of 'slaves, prisoners, and aliens