A council meeting in Moscow in 1917 restored the patriarchate and elected Tikhon days after the Bolsheviks took power, so the office was recovered at the worst possible moment. What followed was the most sustained state campaign against religion anywhere in the twentieth century: separation of church and state on terms that stripped parishes of legal personality, confiscation of church valuables during the famine of 1922, show trials of clergy, and a League of the Militant Godless with millions of nominal members. Thousands of churches in and around the city were closed and used as workshops and warehouses.
The Cathedral of Christ the Saviour, raised over decades in thanksgiving for the defeat of Napoleon, was dynamited in 1931 to clear a site for a Palace of Soviets crowned with a colossal statue of Lenin. The palace was never built; the flooded foundations became an open air swimming pool. In 1943, needing the church's support in the war, Stalin permitted the election of a patriarch again. The cathedral was rebuilt in the 1990s on the same site and reconsecrated in 2000, and it is now where patriarchs are enthroned and buried.
The city holds the Moscow Patriarchate's administration and its principal seminaries, and its religious life extends well beyond Orthodoxy: a Choral Synagogue reopened after the Soviet period, a Cathedral Mosque rebuilt on a far larger scale in 2015 for a Muslim population of migrants and long resident Tatars, and minority religious bodies whose registration has repeatedly been litigated, including a case brought by a Scientology congregation in the city that reached the European Court of Human Rights.