German anti-aircraft forces (dubbed
Flak, an abbreviation of
Flugzeugabwehrkanone, '[anti-]aircraft defense cannon') had been organized in the years 1939 and 1940 into Flak Detachments (), some of which were mobilized for the
Battle of France and placed into the newly formed
Flak Corps (),
I Flak Corps and
II Flak Corps, which were attached to
Army Group A,Army Group A| responsible for the central sector, and
Army Group B, responsible for the northern sector, respectively. In summer of 1942, the German casualties on the
Eastern Front forced military reorganizations. The field armies of the Heer had previously been supported by Luftwaffe commands dubbed
Koluft ("Commanders of the Aerial Forces"), but these staffs were now dissolved. Whereas the home defense had generally been organized by the "Flak Divisions", the two "Flak Corps" had served on the front, without major overlaps between the two. Now, Flak Divisions were also inserted on the frontline, where the flak guns were used not just for anti-aircraft fire, but also to support ground-level combat, notably against enemy armored vehicles. The
12th Flak Division was the first such new mobile Flak division to see action, participating in the battles outside of Moscow in early 1942. Several of the experienced Flak Divisions at home were now to be freed up for frontline action through the formation of new units. In this way, the 2nd Flak Division was sent to the front and replaced by the
14th Flak Division, the
9th Flak Division was mobilized and replaced by the new
13th Flak Division, the
15th Flak Division freed up the
10th Flak Division in Romania, and the
16th Flak Division was formed to free up the
6th Flak Division in German-occupied Belgium. The 2nd, 6th, 9th and 10th divisions were all deployed to the Eastern Front to assist against the counteroffensives by the Red Army. Additionally, the
15th Flak Division,
17th Flak Division and
18th Flak Division were all newly formed and deployed to the Eastern Front as well. In August 1942, the
19th Flak Division was created from the
7th Flak Brigade in
Sicily to assist
Panzer Army Africa. Additionally, the
20th Flak Division was assembled to assist the
5th Panzer Army. Both divisions were soon destroyed in the Axis surrender at the end of the
Tunisian campaign in May 1943. Additionally, the 9th Flak Division on the Eastern Front was destroyed in the
Battle of Stalingrad. A new 19th Flak Division was formed and deployed to
German-occupied Greece in 1943. Likewise, a new 20th Flak Division was sent to
German-occupied Yugoslavia. The
21st Flak Division was newly created (from the
6th Flak Brigade) to replace the 5th Flak Division, which was thus freed up to be deployed to Romania. Other new creations of the year 1943 also included the 22nd Flak Division for the Ruhr area, the
23rd Flak Division for the Eastern Front (formed from the abortive
22nd Luftwaffe Field Division) and, in December 1943, the
24th Flak Division in Vienna, formed through the expansion of the
16th Flak Brigade. The
25th Flak Division was formed in April 1944 on the Italian front by the former
17th Flak Brigade. The
4th Flak Brigade in Munich was expanded in May 1944 to become the
26th Flak Division, bringing the total number of flak divisions at the point of
Operation Bagration and
Operation Overlord in June 1944 to 26. The rapid Allied advances of June and July 1944 caused panicked reorganizations. The 11th Flak Division in France was upgraded to become
III Flak Corps and replaced in September 1944 by a new 11th Flak Division, formed from
15th Flak Brigade. More and more Flak Brigades were now nominally upgraded to become Flak Divisions, resulting in the creation of
27th Flak Division from
11th Flak Brigade in East Prussia in September, the creation of
28th Flak Division from
9th Flak Brigade in Stuttgart in October, the creation of
29th Flak Division in Oslo (German-occupied Norway) from 14th Flak Brigade on 27 February 1945, and the
30th Flak Division, also known as "30th Railway Flak Division", in Berlin in the final weeks of the war, responsible for all railway anti-aircraft units in Germany. == Organization ==