The ROC should not be confused with the Orthodox Church in America (OCA), another autocephalous Orthodox Church (since 1970, albeit not universally recognised in this status), that traces its existence in North America to the time of the Russian missionaries in Alaska (then part of the Russian Empire ) in the late 18th century, and still adheres to the ROC liturgical tradition .

The ROC should also not be confused with the Russian Orthodox Church Outside Russia (also known as the Russian Orthodox Church Abroad, or ROCOR), headquartered in New York, New York , U.S.A. The ROCOR was instituted in the 1920s by Russian communities outside then Communist Russia , which refused to recognize the authority of the Moscow Patriarchate then de facto headed by Metropolitan Sergius Stragorodsky . The two Churches reconciled on May 17, 2007; the ROCOR is now a self-governing part of the Russian Orthodox Church.

The Christian community that developed into what is now known as the Russian Orthodox Church is traditionally said to have been founded by the Apostle Andrew , who is thought to have visited Scythia and Greek colonies along the northern coast of the Black Sea . According to one of the legends, Andrew reached the future location of Kiev and foretold the foundation of a great Christian city. [8] [9] The spot where he reportedly erected a cross is now marked by St. Andrew's Cathedral .