Metropolitan Jonah (ROCOR) gives an informative lecture on the history of Russian Orthodoxy in America.
Ever wonder why there are so many overlapping jurisdictions in North America? American bishops were at a synod in Moscow when Lenin's bolshevik coup started. The bishops were murdered. This decapitated the Orthodox church in America and prevented the fulfillment of unifying differing jurisdictions into a larger body. The results are still visible today.
The communists murdered over 250,000 clergy and 20 million Christians over the course of the Soviet era. As a result ROCOR is perhaps one of the strongest anti-communist organizations in the United States today.