 In the inventory of Orthodox bishoprics compiled under Leo VI (reigned 886 to 912), the see of Rus' ranks sixty-first.In the list compiled during Constantine VII's reign (913-959), the see of Rus' holds the 60th position.The Life of Saint Cyril ("Vita Cyrilli") reports that, when passing through Crimea on his way to Khazaria, the Apostle of the Slavs found in Chersonesos a Bible written in the Rus' language, possibly indicating the existence of a vernacular written tradition as early as the 9th century.