When was the Russian Revolution?

By 1917 Russia was exhausted by World War I, food shortages and anger at Tsar Nicholas II. The February Revolution, which took place in March by the modern calendar, led to the Tsar’s abdication and a provisional government. On 25 October in the old Julian calendar, 7 November in the modern one, Vladimir Lenin’s Bolsheviks seized power in Petrograd in the October Revolution. A brutal civil war followed, and the Bolsheviks eventually founded the Soviet Union in December 1922. The confusing dates exist because Russia only switched to the Gregorian calendar in February 1918.