In particolare la famiglia Ostrogski che detenne il titolo di Grand Hetman di Lituania e contribuì a preservare l'antica lingua slava orientale e l'ortodossia orientale in quella parte d'Europa. ###>The Polish king, Władysław I the Elbow-high, in his letter to the Pope wrote with regret: "The two last Ruthenian kings, that had been firm shields for Poland from the Tatars, left this world and after their death Poland is directly under Tatar threat.