Mezue ahịrịokwu na-esonụ: N'ihi "Anschluss" nke 1938 n'etiti Nazi Germany na Austria, Yugoslavia bịara soro Germany kerịta ókèala ya nke ebe ugwu ọdịda anyanwụ ma daa n'okpuru nrụgide na-arịwanye elu ka ndị agbata obi ya jikọtara onwe ha na ike Axis. N'April 1939, Ịtali mepere ókèala nke abụọ ya na Yugoslavia mgbe ọ
wakporo ma weghara mba Albania dị ha nso. Mgbe Agha Worldwa nke Abụọ malitere, Gọọmentị Royal Yugoslav kwupụtara nnọpụiche ya. N'agbata September na November 1940, Hungary na Romania sonyeere Nkwekọrịta Atọ ahụ, na-akwado ndị Axis, Ịtali wakporo Gris. Ka ọ na-erule n'oge ahụ, ọ fọrọ nke nta ka ọ bụrụ na mba ndị nọ n'Axis na ndị ha na ha na-emekọ ihe gbara Yugoslavia gburugburu kpamkpam, nnọpụiche ya n'agha ahụ bịakwara ka njọ. Ná ngwụsị February 1941, Bulgaria sonyeere Nkwekọrịta ahụ. N'echi ya, ndị agha Germany si Romania banye Bulgaria, na-emechi mgbanaka ahụ gbara Yugoslavia gburugburu. N'ịbụ onye bu n'uche ime ka akụkụ ndịda ya dị nchebe maka mwakpo na-eru nso a ga-awakpo Soviet Union, onye ọchịchị aka ike nke Germany bụ́ Adolf Hitler malitere itinye Yugoslavia n'oké nrụgide isonyere Axis. Na 25 Machị 1941, mgbe oge ụfọdụ gachara, Gọọmentị Royal Yugoslav bịanyere aka na nkwekọrịta ahụ. Ụbọchị abụọ ka e mesịrị, otu ìgwè ndị na-akwado ọdịda anyanwụ, ndị na-akwado mba Serbia nke Royal Yugoslav Air Force wepụrụ onye na-achị mba ahụ, Prince Paul, na a bloodless coup d'état. Ha tinyere nwa nwanne ya nwoke dị afọ iri na ụma bụ Peter n'ocheeze ma weta "ọchịchị nke ịdị n'otu mba" nke onye isi ndị Royal Yugoslav Air Force, General Dušan Simović. Ọgbaghara ahụ kpasuru Hitler iwe, onye nyere iwu ozugbo ka ọ wakpo Yugoslavia, nke malitere na 6 Eprel 1941.