last year I went to Augsburg and I find that the south of Germany is culturally quite distinct from the north.
you are right about comparing the Prussians and the Bavarians (though the Prussians don't exist any more :-P)
hoewver, in the case of Germany, Poland, Belarus, Lithuania and Romania, World War II eradicated those regional differences because millions were just eliminated and the remainder were forcibly mixed
I argue with my Polish wife that now Poland is one people, one religoin etc. but before WWII it was only 68% polish :)
In Poland's case, the communities of Poles in Lwów and Vilnius were simply pushed west -- in some cases to the opposite end to "reclaimed lands" -- reclaimed from Germany
And the Germans, who dreamed of Leibensraum, got the exact opposite -- Baltic Germans who had been living in the Baltics for 7 centuries, were eradicated as was Prussia and the Sudenten Germans
Germans from Romania, hungary etc. were sent to Germany even though they and their great-grandfathers had never seen that land. The mixing of peoples really created one "Germany"
You’re just a bundle of information. Thank you!