Well. Why was it Lithuania (specifically the region around Vilnius and Trakai) that played this role? I say one reason would be its location close to Ruthenia, which had to enable some sort of cultural transfer. At the same time it was relatively safe from the crusaders - before the orders reached them they had to conquer Prussia and Courland, which bought them time the Prussians, for instance, dind't have. A third benefit their location gave them was good access to the divided and better developed Ruthenian principalities, which were ripe for conquest. Prussia or Courland didn't have that. I don't have the data, but it's also likely that the demographic potential of Upper Lithuania was greater than that of Courland or Livonia.
I think Lithuanians were best positioned by far to create a large state in the region, but perhaps some other group could do the same, if external conditions were better for them. Maybe Sudovians, or Prussians if there's no Teutonic Order.
I think Lithuanians were best positioned by far to create a large state in the region, but perhaps some other group could do the same, if external conditions were better for them. Maybe Sudovians, or Prussians if there's no Teutonic Order.