January 1940, both during the Phoney War period in protection of Germany's western border. In 1940, Dickfeld flew missions during the Battle of France and Britain. He was then posted to a Luftwaffe training battalion as a company commander and on 21 February 1941, he was made a war office candidate. He was the posted to the Stab (headquarters unit) of JG 52. On 15 May, III./JG 52 was moved to Athens and together with other Luftwaffe units, flews its first combat missions in support of the Battle of Crete. During this campaign, Dickfeld flew multiple missions against Greek forces and other Allied forces. Eastern Front Following its brief deployment in the Balkan Campaign, III. Gruppe was ordered to Bucharest by mid-June. There, the unit was subordinated to the Luftwaffenmission Rumänien (Luftwaffe Mission Romania) and reequipped with the new, more powerful Messerschmitt Bf 109 F-4 model. On 21 June 1941, the Gruppe was ordered to Mizil in preparation of Operation Barbarossa, the German invasion of the Soviet Union. Its primary objective was to provide fighter protection for the oil fields and refineries at Ploiești. The invasion of the Soviet Union began on 22 June. The next day, the Gruppe moved to Mamaia, the northern district of Constanța on the Black Sea coast. There, Dickfeld claimed his first two aerial victories on 26 June. He was credited with shooting down a Soviet Ilyushin DB-3 bomber and a Tupolev SB bomber in the morning. The Gruppe moved to Belaya Tserkov on 1 August and also used an airfield at Yampil from 6 to 8 August. In August. Dickfeld increased his number of aerial victories to ten, claiming three Soviet fighters on 4 August, one on 11 August, another on 14 August, and two Polikarpov I-16 fighters on 16 August. On 23 October, III. Gruppe moved from Poltava to Chaplynka. The following day, Dickfeld became an "ace-in-a-day" for the first time when shot down five Soviet Polikarpov I-15 fighter aircraft near Ishun. On 19 March 1942, Dickefeld together with fellow JG 52 pilot Feldwebel Edmund Roßmann were awarded the Knight's Cross of the Iron Cross (). On 29 April, III. Gruppe had relocated to Zürichtal, a small village at the Inhul in the former German settlement west of Feodosia in the Crimea. On 1 May, the Gruppe was subordinated to VIII. Fliegerkorps and was supporting the 11th Army in the Battle of the