Galanin was drafted into the Red Army in 1919 and fought as an ordinary soldier in the Russian Civil War.

Galanin then served in several staff positions in the Transbaikal Military District and commanded the 57th Rifle Division during the Battles of Khalkhin Gol in 1939.

He was promoted to command the 17th Rifle Corps in Ukraine in 1940, and held that position when Operation Barbarossa, the German invasion of the Soviet Union, began.

Born on 25 July 1899 in the village of Pokhorovka in Nizhny Novgorod Governorate, Galanin was drafted into the Red Army in April 1919.

He subsequently led a rifle company and battalion of the division and graduated from the Frunze Military Academy in 1936.

Promoted to Major General in June 1940, Galanin was transferred to the Kiev Special Military District to command its 17th Rifle Corps.

From April 1943, he commanded the 70th Army of the Central Front, which took part in the Battle of Kursk and Operation Kutuzov.