The
Russian Orthodox Church (
ROC; ), alternatively legally known as the
Moscow Patriarchate , is one of the
autocephalous Eastern Orthodox churches, in
full communion with other Eastern Orthodox patriarchates. The Primate of the ROC is the
Patriarch of Moscow and all Rus'. The ROC, as well as the primate thereof, officially ranks fifth in the Orthodox order of precedence, right under the four
ancient Patriarchates of the
Greek Orthodox Church, those of
Constantinople,
Alexandria,
Antioch, and
Jerusalem. The official
Christianization of Kievan Rus' widely seen as the birth of the ROC is believed to have occurred in 988 through the
baptism of the Kievan prince
Vladimir and his people by the clergy of the
Ecumenical Patriarchate whose constituent part the ROC remained for the next six centuries, while the
Kievan see remained in the jurisdiction of the Ecumenical Patriarchate until 1686.