The October Revolution , officially known in the Soviet literature as the Great October Socialist Revolution , and commonly referred to as Red October, the October Uprising or the Bolshevik Revolution, was a seizure of state power instrumental in the larger Russian Revolution of 1917. It took place with an armed insurrection in Petrograd traditionally dated to 25 October 1917 (by the Julian or Old Style calendar, which corresponds to 7 November 1917 in the Gregorian or New Style calendar).