Tuhia he haere tonu mō tēnei wāhanga - I whānau a Willius i te 5 o Noema 1919 ki Mainz-Kostheim. Whai muri i te whakangungu paerata, ka tukuna a "Obergefreiter" Willius ki te 2. "Staffel" (2nd squadron) o "Jagdgeschwader" 20 (JG 20<unk>20th Fighter Wing). I taua wa, ko tenei roopu i whakahaua e te "Oberleutnant" Albrecht Freiherr von Minnigerode, katahi ka "Oberleutnant" Fritz Stendel. Ko te "Staffel" i raro i ahau. "Gruppe" (1st group) o JG 20 i whakahaua e "Hauptmann" Hannes Trautloft. I whakawhiwhia te "Gruppe" ki te Messerschmitt Bf 109 E ka whawhai i te Pakanga o Parani i raro i te mana o "Jagdgeschwader" 51 (JG 51<unk>51st Fighter Wing). Whai muri i te Tiriti o te 22 o Hune 1940
Ko ahau. Ko te "Gruppe" o JG 20 i whakauruhia ki roto i te JG 51, ka waiho hei III. "Gruppe" i te 4 o Hurae. Na reira, ka uru a Willius ki te 8. Ko te "Staffel".