The article explores the failed attempt of the all-Orthodox (Ecumenical) Council in the 1920–1930s through the prism of relations between the Constantinople Patriarchate, the Russian Church, and the Soviet government. In the situation of a strong Church discord in Russia, provoked by anti-religious policy of the Bolsheviks, the Patriarchate of Constantinople claimed the role of mediator between the Russian Church (“Tikhonovskaia”) and the Pro-Soviet Renovationist schism.