Rendulic an kira shi zuwa rundunar sojojin Jamus, Wehrmacht, a 1938, bayan da Austria ta haɗu da Jamus. Ya umurci Rundunar Sojoji ta 14 (23 ga Yuni <unk> 10 ga Oktoba 1940); Rukunin Sojoji na 52 (1940<unk>1942); da kuma XXXV Corps (1942<unk>1943), wanda ya halarci yakin Kursk
Ka yi haƙuri. Daga 1943 zuwa 1944, Rendulic ya umurci rundunar 2nd Panzer a lokacin yakin duniya na II a Yugoslavia. A farkon 1944, Shugaban Jamus Adolf Hitler ya umarci Rendulic ya tsara wani shiri don kama jagoran 'yan tawayen Yugoslavia Josip Broz Tito. A sakamakon harin da aka kai kan Drvar a ranar 25 ga Mayu, 1944, 'yan bindigar Jamus sun mamaye hedkwatar' yan tawaye a Drvar (yammacin Bosnia) suna neman Tito amma a ƙarshe sun kasa kama shi, suna fama da asarar rayuka masu yawa.