The decree of January 1918 separated church from state and school from church, nationalised all church property and left religious associations without legal personality, able to borrow back their own buildings on sufferance. The famine of 1921 and 1922 provided the occasion for a direct assault: church valuables were requisitioned for relief, resistance was met with trials, and clergy were shot. The state simultaneously sponsored a rival Living Church to split the hierarchy, and the patriarch Tikhon was arrested.
Anti-religious work then became a permanent institution. The League of the Militant Godless, founded in 1925, ran a mass press, museums of atheism installed in confiscated cathedrals and campaigns against every faith in the union; the law of 1929 confined religious bodies to worship inside a registered building, forbidding charity, teaching and youth work; and the closures accelerated, with the Cathedral of Christ the Saviour in Moscow dynamited in 1931. In the terror of 1937 and 1938 clergy were arrested and executed on a scale Dimitry Pospielovsky documents in detail, and by 1939 only a few hundred Orthodox churches were still functioning in a country that had held tens of thousands.
Nothing about this was confined to Orthodoxy. Mosques, madrasas and Islamic courts were closed across Central Asia and the Caucasus, Jewish religious life was dismantled while Yiddish secular culture was briefly promoted, and Catholic, Lutheran, Baptist and Buddhist institutions were suppressed in turn.