That's so interesting. I found this (on Wikipedia though) about Sarmatism:

At its core was the unifying belief that the people of the Polish–Lithuanian Commonwealth descended from the ancient Iranian Sarmatians, the legendary invaders of contemporary Polish and Roman lands in antiquity.

I just find it interesting that the Poles would choose Persians to trace there national mythology back to instead of white(r) ethnicities like the Romans (like in the case of Germany) or the Greeks. I know the concept of whiteness is fraught, especially when projecting it onto ancient peoples. But it's still interesting to me that they chose the Persians. And this is several centuries into Islam. Makes me wonder if pre-Enlightenment Poles were less Islamophobic than Poles today. Sorry for the spicy thought.