Is it possible for the Habsburgs to annex Prussia through war or marriage? When is the earliest this can be done? Could this be done in spite of the Protestant revolution? Could the Holy Roman Empire be strengthened by this? What else could happen?
before 1600s it's possible, at latest a decisive victory for Catholics in the 30 years war, and for some reason the Habsburg take the Brandenburg throne
Maybe, anything is possibleCould they unite for strategic reasons and be willing to overlook religion?
Old Fritz wanted to marry Maria theresa but then your having Habsburg-Hohenzollerns/Hohenzollerns on the Austrian throne instead of the reverse.Could they unite for strategic reasons and be willing to overlook religion?
Easy. Habsburgs get Polish Crown and then incorporate Ducal Prussia into Polish Crown after death of Albert Frederick.
Heh. That does indeed show the central problem in the question - what even is meant with "Prussia". The realm centred around Brandenburg which merely took its name from the actual Prussia? Or the actual Prussia?I don't know much about the period offhand, but it would certainly be interesting to see what the Habsburgs do with Brandenburg. The most likely would be taking it from the Luxemburgs via marriage (pre the Emperor pawning it), since IIRC it was Wittelsbach for a timr through marriage of a Bavarian prince to a Luxemburg princess
Heh. That does indeed show the central problem in the question - what even is meant with "Prussia". The realm centred around Brandenburg which merely took its name from the actual Prussia? Or the actual Prussia?
Iirc it belonged to the crown of Bohemia until 1417, when an impecunious Emperor leased it to the Hohenzollerns. It was never redeemed.
If that deal isn't made, then butterflies permitting it passes to the Habsburgs with the rest of the Bohemian lands. They might go on to acquire Pomerania, and after that who knows?
Does this allow the Habsburgs to gain more control over the HRE and ensure future successes?
It really depends on your PoD and general situation, but I'll offer this - controlling both Bohemia and Brandenburg gives the Habsburgs two guaranteed votes among the electors. That counts for something
That doesn't seem to be how it works. You couldn't amass electoral votes - or at least, going by the example of when Bavaria (eighth electoral vote after the 30YW) and the Palatinate where united under the same ruler: He still had just one vote. The ceremonial 'office' connected with Bavaria's vote went to Hannover (ninth electoral vote, with an own ceremonial office, but it being even younger it was less prestigeous).It really depends on your PoD and general situation, but I'll offer this - controlling both Bohemia and Brandenburg gives the Habsburgs two guaranteed votes among the electors. That counts for something
That doesn't seem to be how it works. You couldn't amass electoral votes - or at least, going by the example of when Bavaria (eighth electoral vote after the 30YW) and the Palatinate where united under the same ruler: He still had just one vote. The ceremonial 'office' connected with Bavaria's vote went to Hannover (ninth electoral vote, with an own ceremonial office, but it being even younger it was less prestigeous).
That also means that Austria doesn't have to deal with an enemy at its border. Does this allow Austria to conquer better?
They still have to deal with their two main enemies, the Turks and French, though mitigating problems inside the empire by sheer dominance will definitely help
That was because both Bavaria and the Palatinate had the "Palatine Electorate" so when they merged the division became redundant.That doesn't seem to be how it works. You couldn't amass electoral votes - or at least, going by the example of when Bavaria (eighth electoral vote after the 30YW) and the Palatinate where united under the same ruler: He still had just one vote. The ceremonial 'office' connected with Bavaria's vote went to Hannover (ninth electoral vote, with an own ceremonial office, but it being even younger it was less prestigeous).