IMO Polish expansion into Ruthenia was an accident. And disastrous for Poland, at that.
But bck to Kiev - IMO no Mongol battering means:
- Polish-Ruthenian (oh, how I miss the distinction between Rus and Russia the English lacks) border stays as is; Lublin taken by Halitch
It is more perspective, and we do not have a different term for 'Rus' and Russians ourselves, this Ruthenia thing stinks of westerners not being able to pronounce it.
I mean, there is a reason why Mute is used as an ethnonym for Kraut.
And if you look at people like
Bohdan Khmelnytsky, well he saw himself as the rightful ruler of the Rus, nowhere was he mentioning Ruthenians, IIRC.
Anyways, me trying not to start a flame war, time to write some actual ideas.
1. Bulgarians manage to evade the disastrous degradation in relations with Byzantium in the late 10th century, we manage to Christianize and assimilate the Serbian, Zetan and other Slavic tribes on the Balkans while holding to and expanding our positions north of the Danube.
Byzantium is far less inclined to to give the early Rus what they want and even if they come around we beat the shit out of
Sviatoslav when/if he drags his ass, as he put it, "away from the mosquito infested bog that is Kiev and closer to true civilization" , and we gradually expand to the North-East and Christianize the Slavic tribes that would have made up Kievan Rus.
Bonus points if we eventually find a way to assimilate the
other Bulgaria and resist better the attacks of the Mongols.
This would of course require some type of very turbulent situation in Byzantium for about 100 years, preferably them being distracted by the Arabs/other Turkic tribes.