A Flakkorps was a flexible organization that was made up of a varying number of AA regiments, brigades, or divisions.
I Flak Corps withdrew via southern Russia and Crimea in 1943 and through northern Ukraine and Galicia in 1944.
The initial formation was assembled in October 1939 from elements of the 6th Air Division and was deployed near Mönchengladbach at the disposal of Army Group B for the Battle of France.
[2]: 15 After Sea Lion was cancelled, Flak Regiment 136 was withdrawn in October and the entire corps redeployed to Tours on 16 December 1940.
[2]: 96 II Flak Corps participated in the fighting around the Vyazma pocket between 2 and 13 October 1941, shooting down 29 Soviet aircraft, destroying or capturing 14 tanks, 17 bunkers, 104 heavy guns, 18 field fortifications, 5 nests of resistance, 94 machine gun positions, one freight train and 579 motorized vehicles.
23 infantry attacks were repelled and 3,842 Soviet PoWs taken by the members of II Flak Corps.
[2]: 97 In November/December 1943, the II Flak Corps was part of Luftflotte 6, along with Feldluftgau XXVII and Luftwaffenkommando Südost, the latter hosting the German air force mission to Bulgaria.
[2]: 161 The IV Flak Corps was formed in Breslau in June 1944 to support Luftflotte 1 on the Eastern Front.
[2]: 232 The deployment of IV Flak Corps was reattempted in September 1944, this time for the Western Front.
[2]: 285 Initially deployed east of Budapest, V Flak Corps was pushed to Bratislava by December 1944.
[2]: 285 The VI Corps was formed on 10 February 1945 in the north of the Western Front, the sector of Army Group H, from the dissolved 16th Flak Division at Doetinchem.
In 1943 Allied intelligence noted: The Flak Corps is a wartime organization, and constitutes an operational reserve of the commander in chief of the German Air Force.
Although the Soviets also organized large air defense units, they were typically not used against ground targets.
The flak corps above all provided additional antitank support for the German ground forces.
In some cases, such as at Cagny in Normandy, these units achieved significant success against attacking Allied armored vehicles.
As an organizational form, massed AA-gun formations represented a dead-end as large-caliber AA guns were phased out of military service in the 1950s and replaced by surface to air missiles.