Political map of Europe & the Mediterranean 7 November 1917 (October Revolution in Russia): Following the failure of the Kerensky Offensive in July 1917, both left- and right-wing factions vied for power in the weakened Russian state. On November 7 (October 25 in the Russian calendar of the time (Julian calendar)), Vladimir Lenin and his revolutionary Bolshevik party seized power in Petrograd, the capital, and overthrew the government (October Revolution). Simultaneously the Bolsheviks launched armed insurrections across Russia.