Whakaotihia te rerenga e whai ake nei: I te pakarutanga o te Pakanga Tuarua o te Ao i te Mahuru 1939, ka uru a Kopp ki te French Foreign Legion hei corporal ka whawhai ki te Pakanga o France i te Mei-Hune 1940, kaore i ora i te Blitzkrieg kaore i ora i te nuinga o ona hoa. I whara kinotia a Kopp, ā, i mauheretia ia, engari i mawhiti ia i tētahi hōhipera hōia, ā, i taea e ia te hoki atu ki tana waeine, ināianei he
te ope i hinga, i waho noa o Marseilles i Akuhata. I te marama e whai ake nei, i tukuna a Kopp ki te tari matua o te Legion Foreign i Algeria, i reira i whakakorehia ai ia i te ope taua ka whakawhiwhia ki a ia he 80% reti.