The baptism of the Russian state at the end of the 10th century. - one of the fateful periods in all Russian history. With baptism, Rus' overcame tribal “pagan” disunity - a new Christian people was formed, which found its place in world civilization. The book examines various subjects related to the history of early Christianity in Rus': from the pious legend about the path of Andrew the First-Called from the Varangians to the Greeks and descriptions of pagan cults to the construction of architectural masterpieces that completed the process of Christianization - St. Sophia churches in Kyiv, Novgorod and Polotsk.