OK. However, what would have happened afterwards?
For instance, does East Prussia become Russian or get transferred to Poland in exchange for some Polish territory going to Russia? Also, does this completely butterfly away the Partitions of Poland?
Any thoughts on all of this?
The idea was that Russia would give Poland Lithuania East Prussia in return for Courland and a few other minor border fiddles.
Also, how does Russia itself develop with a longer-living Elizabeth?
Elizabeth's health was horrid, she was lucky to live as long as she did. Even if she survives the Seven Year's War Elizabeth is dying a year of two after at most. When Elizabeth dies and Peter inherits his early reign's foreign policy will probably be very different. OTL Peter saved Prussia because he realized that Britain was winning its side of the conflict and that Britain would come out of the Seven Year's War on top. Peter also saw the potential problems caused by removing any German counterweight to Austria.
In the proposed scenario Britain will still come out of the war as the dominate European and colonial power. This means that Peter will have to align himself with Britain to reestablish control over Schleswig. Britain may accept the offer as it will want a continental ally and may have to settle for distant Russia. However Britain might also reject Peter's overtures and instead side with Denmark, which would force Peter to back down in the Schleswig Crisis.
In Germany Prussia will be absolutely demolished. In fact Prussia most likely would no longer be Prussia, it probably would have lost the title of King of Prussia due to the lost of East Prussia, making Prussia once more Brandenburg. As a result Austria's power and influence will be reminiscent of before the Thirty Years' War. Throughout the life of Maria Theresa Austria and France are likely to retain their alliance. Whether Peter retains a friendly Russian relationship with Austria is questionable. OTL Peter allied with Prussia due to its military strength and proximity to Schleswig. Without Prussia being a power of note Peter might decide to retain the Austrian alliance or he might potentially interject himself into German politics and support a collection of lesser German electors and princes against Austrian aggression.
In Russia after Elizabeth's death I don't see many changes to Peter's domestic policies. He is likely to introduce many of the same beloved reforms as he did historically. Whether he is still deposed by Catherine is an open question. Historically Catherine's coup only consisted of two guard regiments that were displeased with the curbing of their power due to Peter's reforms. Peter's alliance with Prussia played no part in the coup, in fact Catherine retained it once she usurped the throne. Which is why I don't see Catherine's coup being any stronger than it was historically. Whether Peter or Catherine wins the struggle for the throne is really only a question of whether Peter fights back. OTL Peter didn't fight back even though he had a superior guard regiment he could have easily defeated the coup with, this was because hen the coup happened his pregnant mistress (whom he loved) was put in danger. With the POD whether his mistress is caught up in the coup or is pregnant may easily be butterflied away. And without that liability I don't see any reason Peter wouldn't unleash his guard on the coup and completely crush it. With such an outcome we would see a widely different Russia. But if Peter's mistress was at risk in the TTL coup and Peter backed down as he did historically then Catherine of course would come to power. I don't see Catherine's domestic policy being much different from her historical one. But without Prussia's interference I would imagine that Catherine's southern ambitions would fare better. Without Prussia threatening Russia whenever it tried to go all out on the Ottomans then all Catherine requires to completely crush the Ottomans in Europe is Austrian approval. Yet any attempt on Constantinople would be blocked by the British navy (unless it was otherwise unoccupied), so no Greek Plan.
Well, there's a decent chance Elizabeth disinherits Peter iin favor of his son (or "son") Paul. Which means at most, Catherine the Great is merely her son's regent, if not packed off to Holstein with Peter.
Not at all. Elizabeth is not disinheriting Peter III. Much of the information that supports that was written after Peter's deposing to legitimize Catherine's reign, Elizabeth would never even have dared disinherit Peter.
I don't think Elizabeth would have disinherited Peter unless she lived long enough for Paul to reach adulthoood - in which case there would be no need for a regent. Even then, assuming Peter and Catherine were still alive, she might have been wary of disinheriting Peter as the aftermath could have led to insurrections and a major destabilising of the throne. It would be difficult for Paul to rule in peace when his father - from whom his Romanov blood came if you ignore the Sergei Saltykov issue - was still alive.
I'm not sure what would have happened re dividing territories. Was Prussia the primary mover in the partitioning of Poland? I think Elizabeth's primary aim - and probably the primary aim of the Austrians too - would be to neutralise Prussia to stop its development into a major power. If the partitioning of Poland were still to happen then it would need to be driven by Russia and Austria and I'm not sure how much of a threat each viewed the country. Poland was already a spent force politically - though I guess it could still have turned things around if it changed its method of government.
She would not have disinherited Peter no matter what and for her to live long enough to see Paul reach adulthood is ASB. Also how would Elizabeth possibly know of the OTL instability that followed Peter's deposing. And I must say any talk of Paul being a Saltykov is quite frankly ridiculous. Everyone knew that Paul was Peter's son, because he looked very much like his father and nothing like Saltykov. Almost all the rumors about Paul's father only emerged after Catherine deposed Peter because she wanted to ruin Peter's image.
Prussia was the primary mover of the partition. Without Prussia, Poland will not be partitioned as Russia enjoys having Poland as a buffer and protectorate.
Was Poland an elective monarchy back then?
Also, in regards to the partition of Poland, if I recall correctly, Prussia was the main instigator of the Second Partition of Poland. I am unsure about Partitions #1 and #3, though.
Yes.
Prussia was the main instigator of the First Partition, not any of the other ones. The Second and Third Partitions occurred because Russia invaded Poland when it got uppity and tried to reform.
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