Pennsylvania
Banned
What do you think would have happened if, instead of siding with Constantinople in the Great Schism of 1054, the Russian Church sided with the Pope and with Rome, ultimately following one of the Eastern Catholic Churches?
Yeah, if it happened anyone involved with it, and their families, would be massacred and the old religion restored, by a rival grand prince if nobody else is up to the deed. The peasants and the army would follow them, as would most of the traditional nobillity
You're exaggerating pretty wildly here. As Kallistos Ware says (and his opinion, as far as I can tell, is pretty representative), "Even after 1054 friendly relations between East and West continued. The two parts of Christendom were not yet conscious of a great gulf of separation between them... The dispute remained something of which ordinary Christians in East and West were largely unaware." Even if the Grand Prince and/or Metropolitan cared enough to issue an official "We think the Pope is right on this one" proclamation, it's highly unlikely that anyone would take this as some sort of definitive break with Constantinople or rejection of Greek contacts, or that the nobility would take sufficient umbrage to cause trouble. The notion of the peasantry rebelling -- or, indeed, even knowing about the alleged schism in the first place -- is even less plausible.
Seriously, the Grand Prince who made such a stupid decision is likely deposed (possibly by death), and replaced by someone sane, who re-sides with Byzantium.
Kiev/Rus 's connexions to 'civilization' were all to the South, mostly through Constantinople. There aren't any 'Catholics' terribly near to connect to (The closest, really are Sweden and Denmark - and that's down rivers and across the Baltic. Moreover, those lands were a) even newer to Christianity than the Rus, and very peripheral to Western Europe/Western Christendom.) Poland doesn't have a border with the Rus yet, and it's a minor state, still.
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