Stab/JG 1 was subordinated to Schumacher's "Jagdfliegerführer" 1 at Jever on 10 May 1940. I. "Gruppe" was assigned to VIII. "Fliegerkorps", and based at Gymnich, Erftstadt, North Rhine-Westphalia. At the tactical level I./JG 1 came under administrative control of JG 27, I./JG 1 but was temporarily put under administrative control of JG 77 on 4 June 1940. It came back under control of JG 27 days later. For the campaign, Stab were assigned four Bf 109s, all operational. I. "Gruppe" were well-equipped with 46 Bf 109 Es but only 24 were combat ready.