According to the History Channel, the Russian revolutions of 1917 led to the withdrawal of Russia from the first World War, a civil war between factions inside Russia, the rise of Vladimir Lenin and the Bolsheviks and the birth of the USSR. It also triggered Marxist revolutions in countries around the world although none were ultimately as successful or long lasting as the Russian revolution.
The Russian revolution actually included two separate revolutions, both in 1917. First, the February Revolution grew out of food riots in the city of Petrograd, now St. Petersburg. When the armed forces were called out to quell the uprising, many of the soldiers defected, forcing Czar Nicholas to abdicate and dissolving the imperial government. Eventually, revolutionaries executed the czar and his family, putting an end to aristocratic rule in Russia. The October Revolution saw Lenin and the Bolsheviks come to power, and they soon signed a peace treaty with Germany. Allied powers supported the anti-Bolshevik factions in Russia in an attempt to bring the country back into the war, but the Bolshevik Red Army faction ultimately prevailed. This costly civil war, in which as many as 10 million people perished, became the cornerstone of Soviet mythology as a tale of their ideological purity in the face of opposition and manipulation by the West and drove much of Soviet policy for decades.