The church reform of Peter the Great happened between 1700 and 1721, beginning the Synodal period that would last until the Russian Revolution of 1917. The early Bolsheviks repressed all institutionalised religions as superstitious oppression of the common people, but Joseph Stalin revived the Church in 1941 when faced with the German invasion. For the remainder of the Soviet Union's existence, the Russian Orthodox Church hierarchy and the Communist Party would collaborate and share power, while dissent was repressed. After the dissolution of the Soviet Union, the Church managed to regain much authority in Russian society, and in cooperation with president Vladimir Putin began promoting the imperialist idea of the Russian world (Russkiy mir) that should reunite to its former glory, especially towards Ukraine, although this contributed to the 2018 Moscow–Constantinople schism that have left the Eastern Orthodox churches around the world divided.[1]