Rubuta ci gaba ga wannan sakin layi - Bayan barkewar Yaƙin Duniya na II, Yarima Paul ya rattaba hannu kan yarjejeniyar kawance a ranar 25 ga Maris, 1941, yana kawo kasarsa cikin sansanin Axis. Rashin amincewa da wannan shawarar, sojojin Yugoslavia sun yi tawaye bayan kwana biyu kuma sun yi shelar mafi yawan matasa Peter II don karɓar cikakken iko. Paul, Olga da 'ya'yansu uku an kama su sannan aka mika su ga' yan Burtaniya, wadanda suka kora su zuwa Girka (inda Sarki George II ya yi maraba da su) sannan kuma zuwa Masar (a karkashin zargin makirci). A lokaci guda, kifar da mulkin Yugoslavia ya sa Hitler ya kai harin bam a Belgrade
da kuma mamaye kasar a watan Afrilun 1941.