1917 The 300-year rule of Romanov dynasty ended with abdication of Tsar Nicholas II during the February-March revolution. Provisional Government lasted from February to October (November, new style) 1917. In October-November the Bolshevik revolution led by Lenin ( Vladimir I. Ulyanov) established a Communist state (named the Union of Soviet Socialist Republics, or USSR, in 1922). Cheka, or Soviet political police, was created to enforce the regime's totalitarian policies.
1918 Constituent Assembly, a popularly elected legislative body, met for only one day in January; was broken up by Lenin because Bolsheviks were only a minority of the body.
1918-1920 Russian civil war, a Communist "Red" victory over non-Communist "Whites," in which some two million Russians perished. Tsar Nicholas II and his family were executed by Bolshevik "Reds" in July 1918.
1921 Gosplan, the state economic planning commission, was created; directed the Soviet economy for almost 70 years, emphasizing heavy industrial production.
1921-1928 New Economic Policy (NEP), Lenin's successful experiment with capitalism, ended under Stalin in 1928.