How might that chunk of the world evolved? The Kievan Rus broke up in the wake of the Mongol invasion, and several city-states emerged in its wake, paying tribute to the Golden Horde; they became a bunch of larger states. This was a power vacuum that could potentially have gone in multiple directions (including a Polish or German invasion, or even a Khazar cultural/national resurgence). In OTL, Moscow emerged as the foremost city of some principality or other, and so the Grand Duke (or whatever his title was; "Tsar" came later) moved his capital to Moscow from some other city, and it became the Principality of Muscovy and later the Duchy (?) of Muscovy, still paying tribute to the Horde. It expanded from there on, eventually taking over what became known as Russia (probably following the same logic that the Mongols had, except that they went mostly in the opposite direction and were largely north of the Mongols). My guess is that someone or a bunch of someones eventually take over the land, but who? And what does the world look like in their wake?