The wing was named after General Walther Wever, the prime pre-war proponent for a strategic bombing capability for the Luftwaffe, who was killed in an aircraft accident in 1936.

III./KG 4 participated in the Battle of the Bzura in which the Polish Army was surrounded and destroyed (largely by the Luftwaffe).

[2] In December 1939 III./KG4 transferred from Nordhausen to Vechta and commenced intensive training for night flying and minelaying operations, while conversion to the Junkers Ju 88 began in February-1940.

II./KG 4 were part of the bomber fleet that flew a "demonstration of strength" raid over Copenhagen on 9 April 1940.

Three Heinkels 111 leading an attack on Waalhaven-airport, Rotterdam in the early morning of May 10 belonged to "Stabsstaffel".

During the Battle of France KG 4 helped paralyse Allied rail networks across Belgium.

After the Belgian capitulation on 3 June KG 4 took part in Operation Paula striking at airfields in and around Paris to destroy the remaining units of the Armée de l’Air.

From 5–19 June, KG 4 attacked harbours and rail targets around Dieppe, and then military columns retreating through the Loire valley and the Tours area.

After the French surrender on 25 June 1940 the unit was ordered to Soesterberg, the Netherlands in July 1940, to begin operations over Great Britain.

On the night of 18/19 June KG 4 lost six Do 17s and He 111s, including Major Dietrich Von Massenbach, Kommandeur of II./KG 4, who was shot down over Norfolk by a Blenheim of 23 squadron flown by Flt Lt Duke-Woolley, He 111 5J+DM crash landed on the beach at Cley Next the Sea, where the entire crew were taken prisoner.

KG 4 had operated a minelaying unit along the British coast and participated in the Blitz and the raids on Coventry on the night of the 14/15 November.

On 29 March 1941 the unit relocated to Wien-Aspern in Austria to begin operations over Yugoslavia and Greece for the coming Balkans Campaign.

A detachment, 4.staffel, under the command of Hauptmann Schwanhauser, was sent to Iraq to support the uprising against the British during the Anglo-Iraqi War.

A notable success occurred on 14 March when the Gruppe attacked a Soviet airfield around Kursk destroying 40 enemy machines and damaging 23 others.

Gruppe was committed to the Southern wing of the front and managed to hit targets over Astrakhan.

In October 1943 the unit was partially equipped with the Heinkel He 177A to perform heavy bomber missions.

In the period 1943-45 the Kampfgeschwader covered the continuous retreat of the Wehrmacht until the end of the war, in the tactical and supply role.