Nicholas II was the last Czar of Russia ruling from November 1st 1894 until abdication on march 15, 1917 when a provincial government was installed in his place because of military defeats, incompetence, and social injustice.
In 1903 the Bolsheviks believed in a radical and elitist revolution and the Mensheviks supported a more progressive change in collaboration with the middle class. Bolsheviks and Menshiviks throw of the tsarists regime and to rid of capitalist.
Lenin in control
The Bolshevik revolution started on November 7th, 1917 and it was led by Vladimir Lenin. His goal was to overthrow the provisional government and set up one for proletariat. Lenin convinced the "reds" to form and immediate insurrection against them and they stormed the Winter Palace. The provisional government had officially fallen into the Bolshevik regime.
The Russian Civil war started in 1918 because many groups had formed against Lenin's Bolsheviks. The red army fought the white army for their form of socialism still lead by Lenin and the whites fought for political monarchism, economic capitalism, and alternative forms of socialism. The red army came out victorious and the rest of the Russian empire was consolidated into the Soviet union.
Lenin became the first leader of the USSR but his health was declining until his death in 1924. Him being gone paved the way for Joseph Stalin, The communist party's new general Secretary. Lenin's inspired leadership is the reason that the Soviet government managed to survive such military odds.
In 1922 Stalin was appointed to the newly created office of general secretary of the communist party. After Lenin's death he set out to take total control, many were exiled and as his paranoia grew he soon conducted a vast reign of terror with people being arrested day and night to be put on trial. the period known as the great purge extended as he grew more paranoid Millions were killed of forced labor and starvation because of his collectivism theory. But he achieved success in forcing a rapid industrialization in which he sent all who resisted to labor camps or to be executed. Its estimated that he killed about 20 million people before his death in 1953.