Three-volume Encyclopedia “Russia during the Civil War 1918 – 1922” (Moscow: Political Encyclopedia, 2021) was published. It is a fundamental scientific work, which presents the military, political, economic, and cultural processes that took place in the country in 1918 – 1922. The publication includes over 2900 entries about the events of the civil war, considered in the context of a wide panorama of the life of this period. The encyclopedia contains about 2000 rare photographs, photographs of paintings, sculptures, maps, diagrams, plans of military operations, graphic works. The team of authors of the project consisted of more than 50 researchers representing archives, academic institutes, museums, universities of Russia, Belarus, Ukraine. The encyclopedia aims at everyone interested in the military, political, economic, and cultural history of Russia. Doctors of historical sciences, leading researchers of the Department of the modern history of St. Petersburg Institute of the Russian Academy of Sciences V.I. Musaev and E.D. Tverdyukova took part in its composure.