During the civil war, the workers form groups called soviets. These soviets gave workers identity as people coming together for a common purpose. 
April 1917 Stalin and Lenin
In 1916, Russian women had to watch their crops rotting in the field because so many men are fighting in the WWI and there are not enough hands to harvest crops.  People are angry, so they decide they would protest and start a revolution. 
November 1917 Lenin and Bolsheviks
During the civil war, the workers form groups called soviets. These soviets gave workers identity as people coming together for a common purpose. 
Trotsky’ Contribution
After Stalin was appointed Bolshevik Central Committee in April 1917, Stalin helped Lenin to evade from capture from authorities. Later, Stalin help seized Petrograd and he was appointed People’s Commissar for Nationalities Affair. 
In November 1917, Lenin led the Bolsheviks and took control of the capital Petrograd. They removed Provisional Government and continued fighting their opponents until 1921. Additionally, Russia under their control signed a treaty with Germany to stop German invasion of Russia. This turned out to be a very good decision. 
From March 1918 to January 1925, Trotsky leaded the Red Army as People's Commissar for Military and Naval Affairs. He had great contribution for the Bolshevik victory in the Russian Civil War of 1917–1922. He became one of the seven members of the first Bolshevik Politburo in 1919.