Silesia and Pomeranian are key examples- IIRC the Catholics Poles in Prussia were less radical than the Protestants. The religious tensions are pretty important... but then again the religous defiance was basically a finger in the Emperor.. There's a reason they are known as Bohemians.
So the challenge (from a 14th century perspective) is to get a Habsburg Austria Hungary with incentive to break with Rome.
The easiest way would be to make the Habsburgs divorced from Spain and Italy but still inherit Burgundy, Bohemia and Hungary. OTL the Habsburgs had to keep a firm party line to the Catholic Church because of the Spanish alliance and the integral role of the pope in Italy and the Empire.
So let's have two divergences. If Gian Galeazzo succeeds in claiming North Italy and eventually inherits the Angevin claims on Naples (and Provence?) This creates a powerful state that can wrest control of Italy and the privilege of the Roman Empire from the German king. Secondly gimp France and wank Burgundy- let Charles the bold secure a royal crown and keep the HYW going on longer to prevent France from protesting much in the interim. Aragon doesn't unite with Spain, and gets partitioned between Castille and France. Castille unites with Portugal and generally stsys out of European affairs.
Then have the Habsburg branch under Laszlo the Posthumous (the leopoldines?) survive, giving them Austria, Hungary and Bohemia half a century earler. This branch inherits Burgundy. Meanwhile France allies Italy and the Habsburgs ally England and maybe Spain.
By the time the Reformation comes around the Habsburg territories are hotbeds of the Reformation and antagonistic to France, Italy and the Pope. Thus Protestantism becomes a marker of pro-Habsburg affiliations and Catholicism anti-Habsburg.
Alternately a more permanent Mongol conquest of Hungary could do to Germany (and Italy) what the Golden Khanate did to Russia. Give Ogedai another decade of life and they basically own the Balkans and are raiding constantly into Italy, Bohemia, and Bavaria like a medieval Ottomans.
So the challenge (from a 14th century perspective) is to get a Habsburg Austria Hungary with incentive to break with Rome.
The easiest way would be to make the Habsburgs divorced from Spain and Italy but still inherit Burgundy, Bohemia and Hungary. OTL the Habsburgs had to keep a firm party line to the Catholic Church because of the Spanish alliance and the integral role of the pope in Italy and the Empire.
So let's have two divergences. If Gian Galeazzo succeeds in claiming North Italy and eventually inherits the Angevin claims on Naples (and Provence?) This creates a powerful state that can wrest control of Italy and the privilege of the Roman Empire from the German king. Secondly gimp France and wank Burgundy- let Charles the bold secure a royal crown and keep the HYW going on longer to prevent France from protesting much in the interim. Aragon doesn't unite with Spain, and gets partitioned between Castille and France. Castille unites with Portugal and generally stsys out of European affairs.
Then have the Habsburg branch under Laszlo the Posthumous (the leopoldines?) survive, giving them Austria, Hungary and Bohemia half a century earler. This branch inherits Burgundy. Meanwhile France allies Italy and the Habsburgs ally England and maybe Spain.
By the time the Reformation comes around the Habsburg territories are hotbeds of the Reformation and antagonistic to France, Italy and the Pope. Thus Protestantism becomes a marker of pro-Habsburg affiliations and Catholicism anti-Habsburg.
Alternately a more permanent Mongol conquest of Hungary could do to Germany (and Italy) what the Golden Khanate did to Russia. Give Ogedai another decade of life and they basically own the Balkans and are raiding constantly into Italy, Bohemia, and Bavaria like a medieval Ottomans.