[1][2] Joining the Imperial Russian Army during World War I in September 1914, Managarov was assigned to the 5th Reserve Cavalry Regiment at Balakleya as a ryadovoy.

[3] After the February Revolution, Managarov joined the Yenakiyevo Red Guard Detachment, formed from miners, in August 1917, and was chosen as its commander due to his combat experience.

After a stint as a military advisor in Xinjiang from January 1936 to June 1938, he returned to the Soviet Union to command the 8th Cavalry Division of the 1st Separate Red Banner Army of the Far Eastern Front.

[1][4] After Operation Barbarossa began, Managarov remained in the Far East with the division, and was appointed commander of the 26th Rifle Corps of the army in November 1941.

The corps spent the rear in the front reserve and in December Managarov became commander of the 41st Army, which he led in the Rzhev-Vyazma Offensive.

[4] While at the observation post of the 116th Rifle Division during fighting to the northeast of Kirovograd on 5 December, Managarov was severely wounded by a German shell that killed the army artillery commander and the chief of the operations department.

[6] In July, front commander Army General Rodion Malinovsky evaluated Managarov as an "observant and disciplined commander" and a "brave and decisive general with strong willpower and steady character" who showed initiative in both defensive and offensive operations, but tempered this praise with the statement that Managarov exhibited "insufficient operational thinking".

[7] Managarov received the title Hero of the Soviet Union and was awarded the Order of Lenin on 28 April for his "skillful command of the army" and "personal courage and heroism" in the fighting to break through German defenses in the area of Hodonín and the crossing of the Morava, being promoted to colonel general on 29 May.

[3] After the end of the war in Europe, Managarov and the 53rd Army were relocated to the Far East to participate in the Soviet invasion of Manchuria with the Transbaikal Front.

During the invasion, the army broke through the Japanese border fortifications to cross the Greater Khingan, capturing Dandong and Chaoyang.