Political map of Europe & the Mediterranean 1 December 1917 (Bolsheviks Gain Control in Russia): By December 1917, Lenin's (Vladimir Lenin) Bolsheviks (Bolshevik) controlled many of the major cities of Russia and the Republic had collapsed. Resistance was strongest amongst the various Cossack hosts (Cossack host), the Menshevik forces (Menshevik) in Transcaucasia, and the independence movements among many of Russia's ethnic minorities.