In 1918 Berzarin enlisted in the Red Army and fought against Allied troops in Archangelsk. Between 1921 and 1923 he received more military training at the Leningrad Command Courses, machine gun course at the "Vistrel" and a command course at the Siberian Military District. In 1922, he became a member of Komsomol. In 1923 he was assigned to Siberia.