Rubuta ci gaba don wannan sakin layi - Bayan "Anschluss" na 1938 tsakanin Jamus da Austria, Yugoslavia ta zo ta raba kan iyaka tare da Reich na Uku kuma ta faɗa cikin matsin lamba yayin da maƙwabtanta suka haɗa kansu da ikon Axis. A watan Afrilu na 1939, Italiya ta buɗe iyaka ta biyu tare da Yugoslavia lokacin da ta mamaye kuma ta mamaye makwabciyar Albania. Da aka soma Yaƙin Duniya na II, gwamnatin Yugoslavia ta sanar da tsakatsakinta. Tsakanin Satumba da Nuwamba 1940, Hungary da Romania sun shiga Yarjejeniyar Tripartite, suna daidaita kansu da Axis, kuma Italiya ta mamaye Girka
Ka yi haƙuri. Tun daga wannan lokacin, Yugoslavia ta kusan kewaye da iko na Axis da kuma tauraron su, kuma matsayinta na tsaka tsaki game da yaƙin ya zama mai wahala. A ƙarshen Fabrairu 1941, Bulgaria ta shiga cikin Yarjejeniyar. Kashegari, sojojin Jamus sun shiga Bulgaria daga Romania, suna rufe zoben da ke kewaye da Yugoslavia. Da yake niyyar tabbatar da kudancinsa don kai hari kan Tarayyar Soviet, Adolf Hitler ya fara matsa lamba ga Yugoslavia don shiga Axis. A ranar 25 ga Maris, 1941, bayan wani jinkiri, gwamnatin Yugoslavia ta sanya hannu kan yarjejeniyar. Kwana biyu bayan haka, wasu gungun masu goyon bayan Yammacin Turai, 'yan kishin ƙasa na Serbia Royal Yugoslav Army Air Force jami'ai sun hambarar da mai mulkin kasar, Yarima Paul, a cikin wani juyin mulki mara jini, ya sanya dan dan uwansa matashi Peter a kan karagar mulki, kuma ya kawo "gwamnatin hadin kan kasa" karkashin jagorancin Janar Dušan Simović. Wannan juyin mulki ya sa Hitler fushi, wanda nan da nan ya ba da umurni a mamaye ƙasar. Lokacin da juyin mulkin ya faru, Helm ya ziyarci Berlin, kuma Kraus yana cikin Belgrade.