The
12th Army (1st Formation) (RKKA) of the Soviet
Red Army was formed from the Southern (Cavalry-Mechanised) Army Group of the Kiev Special Military District during 1939–40. It was then involved in the
Soviet invasion of Poland in 1939. It entered the
Second World War as part of the
Soviet Southwestern Front, comprising the •
13th Rifle Corps (including the
44th,
58th, and
192nd Rifle Divisions) •
17th Rifle Corps (
60th Mountain,
69th Mountain, and
164th Rifle Divisions), •
16th Mechanised Corps (
15th,
39th Tank Divisions,
240th Mechanised Division) • 10th, 11th and 12th Fortified Regions, and artillery, engineering and other units. It participated in the frontier battle to the west of
Stanislau. In the second half of July as part of the
Soviet Southern Front it conducted defensive fights in the direction of
Uman. During the
Battle of Uman, the Twelfth Army was caught in a huge encirclement south of
Kyiv along with the
6th Army. Thus the army's headquarters was disbanded on 10 August 1941, after the battle. The 12th Army was reformed in August 1941 as part of the
Soviet Southern Front on the basis of 17th Rifle Corps. The Army defended the left bank of the
Dnepr around
Zaporozhye, from the end of September to the beginning of December, 1941. It participated in the
Donbas defensive,
Rostov defensive and offensive, in January, 1942 in the
Barvenkovo–Lozovaya Offensive operations, in the subsequent conducted defensive fights in Donbas and on Northern Caucasus (part of the
Battle of the Caucasus). In the middle of April 1942 the
261st Rifle Division under Colonel A.M. Ilyin, the
4th Rifle Division (Colonel
Ivan Rosly), the
74th Rifle Division under General F.E.Sheverdin, the 176th Rifle Division (General Vladimir Martsinkevich) and 54th Tank Brigade under Colonel K.S. Minarov were assigned to the Army. It was later in 1942 reorganised as a defensive zone HQ, but then reformed again by conversion of the previous
5th Tank Army in mid April 1943. It joined the
Southwestern Front. Its structure included the
172nd,
203rd,
244th,
333rd and
350th Rifle Divisions and other formations. In April – July the Army was in Front reserve, and then participated in the Donbas and Zaporozhye offensive operations. In November the army HQ was disbanded, with its forces transferred to other armies. ==Commanders==