The Russian Revolution is the collective term for the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. In the first revolution of February 1917 (March in the Gregorian calendar) the Czar was deposed and replaced by a Provisional government. In the second revolution of October that year the Provisional Government was removed and replaced with a Bolshevik (Communist) government.
The February Revolution (March 1917) was a spontaneous popular revolution focused around St Petersburg. In the chaos, members of the Imperial parliament or Duma assumed control of the country, forming the Russian Provisional Government. The army leadership felt they did not have the means to suppress the revolution and Czar Nicholas II of Russia, the last Czar of Russia, abdicated, effectively leaving the Provisional Government in power. The Soviets (workers' councils) which were led by more radical socialist factions initially permitted the Provisional government to rule, but insisted on a perogative to influence the government and control various militias. The February Revolution took place in the context of heavy military setbacks during the First World War, which left much of the army in a state of mutiny.
A period of dual power ensued, during which the Provisional Government held state power while the national network of Soviets, led by socialists, had the allegiance of the lower-class citizens and the political left. During this chaotic period there were frequent mutinies and many strikes. When the Provisional Government chose to continue fighting the war with Germany, the Bolsheviks and other socialist factions campaigned for the abandonment the war effort. The Bolsheviks formed workers militias under their control into the Red Guards (later the Red Army) over which they exerted substantial control.
In the October Revolution (November on the Gregorian calendar), the Bolshevik party, led by Vladimir Lenin, and the workers' Soviets, overthrew the Provisional Government in Petrograd. The Bolsheviks appointed themselves as leaders of various government ministries and seized control of the countryside, establishing the Cheka to ruthlessly quash dissent. To end the war, the Bolshevik leadership signed the Treaty of Brest-Litovsk with Germany in March 1918. However a brutal civil war erupted between the "Red" (Bolshevik), and "White" (anti-Bolshevik), factions, which was to continue for several years, with the Bolsheviks ultimately victorious. In this way the Revolution paved the way for the USSR. While many notable historical events occurred in Moscow and Petrograd, there was also a broadly-based movement in cities throughout the state, among national minorities throughout the empire, and in the rural areas, where peasants took over and redistributed land.
Bolshevik forces marching on Red Square.