Let's assume that, for some reasons, Clement VII accepts Gustav Vasa's candidate as Archbishop of Uppsala and that this is enough to keep Sweden Catholic.
How would this PoD influence OTL's Swedish rise to power, involvement in the TYW and in the Baltic region?
 
Could it be possible that in this scenario, Sigismund III Vasa (or rather his ATL twin) manages to keep the balance of being king of both Sweden and Poland? While there was definitely a political aspect to the challenges he faced (king vs. Parliament), I feel that removing the religious conflict of interest between mostly Lutheran Sweden and mostly Catholic Poland could give him a political boost. I'll admit it's not an area I'm very expert on though.

Sweden and Poland with a union of crowns is the sort of dream that military wanks are made out of, though for the Russians and Hapsburgs it would be the stuff of nightmares.
 
Actually I thought about an alt-Sigismund keeping both thrones, but not being an expert too, I've no idea about the possible consequences.
Maybe his sons' kingdoms would be more focused on the Baltic.
 
Actually I thought about an alt-Sigismund keeping both thrones, but not being an expert too, I've no idea about the possible consequences.

I think a likely scenario is that it butterflies Russia as we know it, since a united Polish/Swedish military during Russia's Time of Troubles is going to be able to run roughshod over them (OTL they were fighting a war against each other while trying to occupy Russia). As per OTL, I don't think they'd be able to hold Russia if they try to force the people to convert to Catholicism, but a different turn of the war could remake Russia. For example, the PolSwed army could destroy Moscow as a city rather than abandoning it and allow another city to become the center of power in Russia such as Tver.
 
I'm not sure about Moscow being destroyed, but I agree that possible alternative Russian capitals too close to Poland-Lithuania-Sweden would be really at risk and that Russia in general would be screwed.
This creates an interesting scenario for the Ottomans in the South.
 
More Russian expansion to the South and South East perhaps?
This is also a possibility, but in the XVII century, AFAIK, Russia alone couldn't match the Ottomans.
Perhaps this alt-Russia after the Time of troubles would be more Asian-focused and, if Moscow is lost or sacked as twovultures said, a city located further East could become capital.
 
Gustav Eriksson (Vasa)/Gustav I will be wanting (and needing) church property for his centralisation of the Swedish state - without it, Sweden will be a weak and ineffectual country unable to project any kind of power anywhere. If church property is not siezed by the crown, the crown does not have the means to take on the independent-minded and revolt-happy peasantry nor the feuding and coup-happy nobility. Sweden will continue to be a 3rd or 4th rate power at the outskirts of Europe, relevant only for the production of some naval supplies for the Hansa and eventually the Dutch and English and for the Danish monarchs constant attempts at subduing it.
 
The obvious counter-question is, how come the entirety of Scandinavia went Protestant, even under 2 separate dynasties, as did northern Germany? It couldn't exactly be pure cuius regio eius religio or else the Protestant vs. Catholic division would've been far more of a patchwork than it was on the eve of the Thirty Years' War.
 
Sweden and Poland with a union of crowns is the sort of dream that military wanks are made out of, though for the Russians and Hapsburgs it would be the stuff of nightmares.

@Jan Olbracht can confirm or refute this, but if Gustaf Vasa stays Catholic, Sigismund I will have to find another reason why he can't let Hedwig (his eldest daughter) marry Gus. OTL Sigismund refused due to the fact that Gus was a Protestant.
This of course means that the entire Vasa line as we know it might be butterflied (since ICR if Gustaf proposed to Hedwig as a first or second wife).

PS: And it would turn into a TRUE nightmare down the road if a king of Sweden-Poland-Lithuania decides to remember Hedwig's Zapolya blood and claim the crown of Hungary as well.
 
@Jan Olbracht can confirm or refute this, but if Gustaf Vasa stays Catholic, Sigismund I will have to find another reason why he can't let Hedwig (his eldest daughter) marry Gus. OTL Sigismund refused due to the fact that Gus was a Protestant.
This of course means that the entire Vasa line as we know it might be butterflied (since ICR if Gustaf proposed to Hedwig as a first or second wife).

PS: And it would turn into a TRUE nightmare down the road if a king of Sweden-Poland-Lithuania decides to remember Hedwig's Zapolya blood and claim the crown of Hungary as well.
As Catholic Gustav would be no worse candidate for hand of Sigismund's daughter than Janos Zapolya was.
There is other scenario for Catholic Sweden-Sigismund Jagiellon was offered Swedish throne by Swedish rebels around 1506, but after Sigismund inherited thrones of Lithuania and Poland and after he improved relations with Denmark nothing came from that plans. But if Sigismund's brothers lived longer he is likely to accept Swedish offer (having nothing better to do as crownless fifth son) thus instead of Sigismund Vasa on Polish throne there would be Sigismund Jagiellon on Swedish throne.
 
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