The Red Army is the defense of the proletarian revolution.
Soviet Posters of the era of the Civil War 1918-1921 by B.S. Butnik-Siverskii (1960), page 267, poster 1240.
Stites, R. (1991). Revolutionary dreams: Utopian vision and experimental life in the Russian Revolution. New York: Oxford University Press. (hammer and plough symbol)
The artist's name on the poster is not indicated. By assigning Artist Unknown to a poster it also could mean the artist used a chop mark whereby no signature is seen thus rendering the artist's identity anonymous.
The Union of Communes of the Northern Region (SKSO) was a political zone encompassing Petrograd, Novgorod, Pskov, Olonets, Arkhangel’sk, and the provinces of Vologda, Severodvinsk and Cherepovets along with Severnaia Oblast and Severnaia Commune. SKSO was based on an association of Soviets (local councils) that existed from April 1918 until February 1919. It was formed in Petrograd (St. Petersburg) at the First Congress of Soviets of the Northern Region-- held April 26–29, 1918. The congress elected a central executive committee and it confirmed an executive body (the Council of Commissars of the Northern Commune) based on departments existent in the Petrograd Soviet. While political differences in the region helped to erode the Union of Communes, its key dissolution occurred when the central government was relocated from Petrograd to Moscow. On February 24, 1919, the 3rd Congress of Soviets of the Northern Region abolished the Northern Region as a political zone.