Yeah they don't show up at all when starting new playthrough.

not working

0/10 not enough pope

@WolfAleron _______ can u see date??? 450? so it's why it's not catolic and I hope never will be

Why they're not Catholic?

It's "a very tiny ENORMOUSLY" inaccurate :P. Yes, our "less prominent" ancestors lived there, but they were germanic Lugians, Vandals etc.
Our "more prominent" ancestors Slavs (the Wendish branch) lived most likely on the today's Ukrainian-Belarussian border, and moved there after most Germanics and remnants of Celts migrated westward. Then the Slavs assimilated the remnants. Even then, they were primarily Slavs, perhaps of some today's unknown tribal denomination, but you wouldn't tell "Poles" apart from future "Russians" or "Croats" or whatever.
If you want to play a Turboslav, why not to create the entire Lechian Empire and be done with it :P ? This aside, I'd like having a Wendish tribe somewhere, and it's a good start.

Ancient Poles lived in this territory for centuries, what does not make sense in your opinnion?

This doesnt make sense in any way but thank you.

I hope they're Catholic as well.