The book examines the history of the Soviets of Workers' and Soldiers' Deputies, their composition and structure, as well as the activities of Bolshevik factions in the Soviets. The work of the Soviets during the peaceful development of the revolution, after the liquidation of dual power, during the Kornilovism and on the eve of the Great October Socialist Revolution is covered in detail. The large documentary material shows the huge role of the Soviets in the preparation and organization of the October armed uprising in the country.