Originally posted by warsfan
If said union does last, I expect it could eventually take over Silesia and Polonise/Czechify it. Again, assuming it lasts without too many internal problems, Brandenburg, Austria, Saxony, and Prussia all seem like good targets for expansion.
What are the chances such a union could last, and eventually centralize, though? And if it did, where would the capital be-Prague? Warsaw? Krakow?-and who would be most likely to become the "dominant" partner, Czechs or Poles?
Seems like an interesting POD-if Bohemia/Poland lasts and does any serious expansion, I can see it re-slavicising large parts of eastern Germany and Austria.
Silesia would have been taken quite quickly, since Silesian dukes usually balanced between Poland and Bohemia. In case of PBU, they would have become PBU vassals.
As far as potential expansion I do not think PBU would have attack Prussia - in fact, I suspect that relations with teh Teuonic Order would have been quite good. If Vencesalus III lives, the Order would have probably never taken Pomerelia.
Initially the "dominant"partners would have been the Bohemians - and that might have destroyed PBU very early. Venceslaus II was rather unpopular in Poland so his son would have needed to gain support of at least a part of Polish leaders. I think it would have been possible - nominate more Poles for important positions (Vencesalus II nominated mostly Germans, even in Bohemia), protect Pomerelia from Brandenburg, etc.
The capital, at least in the beginning, would have been in Prague. At the time Bohemia was stronger and richer. Later, more populous Poland might take over and the capital slowly might be transferred to Cracow, thanks to its better geographical position to rule both kingdoms. Warsaw is out of the question, since it was a small village at the time. IOTL it later became the capital of the PLC since it was closer to Lithuania (and Sweden, in time of Vasas).
As far as expansion goes, I wouldn't be surprised if PBU was interested in Meissen and Lusatia. PBU night have also decide to go against Brandenburg and dominate Pomerania, possibly also part of Austria (Styria?)
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