Ispired by discussion in Bavaria Unites Germany thread:
https://www.alternatehistory.com/forum/threads/ahc-bavaria-unites-germany.458221/

As title says, Holy Roman Emperor Maximilian I can't have children. Serious changes would start after his marriage with Mary of Burgundy, which would obviously remain childless. That is certainly change significant enough to butterfly away Mary's horse ridding accident, so let's say Mary outlives Max ITTL. So Maximilian's obvious heirs would be his nephews, sons of Kunigunde of Austria and Albert IV of Bavaria. But after Mary's childless death there is no clear successor of Burgundian Inheritance, Max surely would want to secure succession of his nephew also there (with what effect?). Max' position in Low Countries is both better (Mary lives) and worse (no kids by Mary). Claims of Wilhelm of Bavaria would be really weak, Mary is just his aunt by marriage, but someone have to rule Netherlands, and Wittelsbach should be more acceptable than other alternative: French rule. Inheriting Habsburg lands Wittelsbchs should also get support of Fuggers (who had copper mines in Tirol) during Imperial Election, this, and close kinship with previous Emperor, should be enough to ensure victory. Austro-Bavaria would be far bigger than any other state of HRE, especially if Low Countries are added, but it is still not as good as IOTL Austria + Bohemia (Bohemia has given Habsburgs royal title and Electoral vote), but there is solid unification of Southern Germany at least, unless lands are divided again: Maximilian had two nephews. And there are going to be massive changes in surronding countries, and also in Iberia (no double Habsburg-Trastamara marriages) and England...
 
Ispired by discussion in Bavaria Unites Germany thread:
https://www.alternatehistory.com/forum/threads/ahc-bavaria-unites-germany.458221/

As title says, Holy Roman Emperor Maximilian I can't have children. Serious changes would start after his marriage with Mary of Burgundy, which would obviously remain childless. That is certainly change significant enough to butterfly away Mary's horse ridding accident, so let's say Mary outlives Max ITTL. So Maximilian's obvious heirs would be his nephews, sons of Kunigunde of Austria and Albert IV of Bavaria. But after Mary's childless death there is no clear successor of Burgundian Inheritance, Max surely would want to secure succession of his nephew also there (with what effect?). Max' position in Low Countries is both better (Mary lives) and worse (no kids by Mary). Claims of Wilhelm of Bavaria would be really weak, Mary is just his aunt by marriage, but someone have to rule Netherlands, and Wittelsbach should be more acceptable than other alternative: French rule. Inheriting Habsburg lands Wittelsbchs should also get support of Fuggers (who had copper mines in Tirol) during Imperial Election, this, and close kinship with previous Emperor, should be enough to ensure victory. Austro-Bavaria would be far bigger than any other state of HRE, especially if Low Countries are added, but it is still not as good as IOTL Austria + Bohemia (Bohemia has given Habsburgs royal title and Electoral vote), but there is solid unification of Southern Germany at least, unless lands are divided again: Maximilian had two nephews. And there are going to be massive changes in surronding countries, and also in Iberia (no double Habsburg-Trastamara marriages) and England...

Wasn't there a male-line cousin of Mary's still running around soemwhere in France (the comte de Nevers or somesuch)? I'd imagine he's the go-to for heir to Burgundy. Austria might not all go to Bavaria. When Ladislaus the Posthumous died, AIUI, some of his lands went to his sister, but others went to a distant cousin (Friedrich III). Same for when Karl VI died. Bavaria and Saxony were seen as having rights superior/equal to Maria Theresia (who was the daughter of the last emperor).
I wouldn't be surprised if there's a sort of split between Bavaria (heirs of Max's sister), Baden and Saxony (heirs of Friedrich III's sisters), not to mention I could see Elisabeth of Austria, Queen of Poland pushing one of her sons to make a play for the territories formerly belonging to her late brother
 
Wasn't there a male-line cousin of Mary's still running around soemwhere in France (the comte de Nevers or somesuch)? I'd imagine he's the go-to for heir to Burgundy. Austria might not all go to Bavaria. When Ladislaus the Posthumous died, AIUI, some of his lands went to his sister, but others went to a distant cousin (Friedrich III). Same for when Karl VI died. Bavaria and Saxony were seen as having rights superior/equal to Maria Theresia (who was the daughter of the last emperor).
I wouldn't be surprised if there's a sort of split between Bavaria (heirs of Max's sister), Baden and Saxony (heirs of Friedrich III's sisters), not to mention I could see Elisabeth of Austria, Queen of Poland pushing one of her sons to make a play for the territories formerly belonging to her late brother
Hungarian-Bohemian Jagiellons could claim Austria proper (unless there is some retard like Lajos II on the throne in Buda) they're close to Vienna at least, unlike Saxons. There could be Jagiellon-Wittelsbach war over Austria.
Male line cousin of Mary was John II Count of Nevers, but he died in 1491, as I've pointed in OP Mary is not going to die in horse ridding accident, so she'll outlive him, his female line descendants were Dukes of Cleves, but there is something more needed to enforce claim than genealogy-power must support such claim, otherwise it is situation like with Ranuccio Farnese and Portuguese succession.
 
In Iberia things could go like this: Spanish-Imperial match is impossible, Max have no kids and his nephews and nieces are too young, so maybe Isabella (daughter of Catholic Monarchs) is allowed to became nun while Joanna takes her place as Manuel's wife, Maria could marry in Savoy, Naples (if Naples' Trastamaras are not deposed) or Bohemia-Hungary (that last option seems least likely). Juan of Asturias could marry Joanna of Naples or die unmarried.
If something like First Congress of Vienna is going to happen ITTL position of Maximilian would be weaker (Maximilian's successor is not going to inherit Spain and his succession in Low Countries is dubious), still Burgundian Inheritance would not be Wittelsbach's problem immediately after death of Max, because Mary of Burgundy would outlive him like OP says.
 
The Sole Heir of The Most Catholic Majesties are NEVER going to remain unwed... Juan will have another bride, he's the most desirable groom in Europe at this time.
 
The Sole Heir of The Most Catholic Majesties are NEVER going to remain unwed... Juan will have another bride, he's the most desirable groom in Europe at this time.
Portugal, France, England and HRE have no one of right age to offer, Joanna of Naples is perfect agewise, if Juan is waiting for younger candidate, he'll simply not live long enough to marry.
 
Joanna of Napels is perfect then. Or Catherine of Navarre.
Catherine of Navarre will not marry him so Juana of Naples is the only realistic choice (pity she is so closely related to him being his first and also second cousin as her parents also were first cousins)
 
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