KG 55's units began a last minute withdrawal to the Eastern borders of the Reich in preparation for Operation Barbarossa, the war on the Soviet Union. It was assigned to "Fliegerkorps" V (5th Flying Corps), subordinated to "Luftflotte" 4. The Stab. unit had six He 111s, all operational and two Messerschmitt Bf 110s, with one operational. I., III. Gruppe and the "Geschwaderstab" moved from their respective bases to Zamość in Poland, while II "Gruppe" was located to Klemensów aerodrome south east of Lublin in Poland under the command of Major Ernst Kühl, who assumed command on 31 March 1941. I./KG 55 had all 27 He 111s operational, II./KG 55 reported 22 of 24 bombers ready for action, and the third group 24 of 25 operational on 22 June 1941. On 8 March 1941 the "Erganzungstaffel" was formed into IV. "Gruppe", but was deployed to Dijon in France and remained there until 4 May 1944. was to provide air support for Army Group South attacking into the Ukraine in its drive toward the Caucasus and the Soviet oil fields.