Answer:
Greek Missionaries of the Orthodox Church visiting neighbouring countries to learn the languages, and spread the word of God. Christianity was carried into Kyivan Rus by missionaries from Byzantian in the 9th century. Saint Methodius and Saint Cyril were the first to start the spreading Christianity among the Slavs by converting the Bible into Slavonic. Patriarch Ignatius (Photios I of Constantinople) tried to spread Christianity by sending Christian bishops in Novgorod.