Kammala jumla mai zuwa: Daular Japan ta mamaye wasu sassan kasar Sin a shekarar 1937, wanda ya haifar da yakin Sino-Japan na biyu (1937 <unk> 1945). A cikin 1940, Daular ta mamaye Indochina ta Faransa, bayan haka Amurka ta sanya takunkumin man fetur a kan Japan. A ranar 7 zuwa 8 ga Disamba, 1941, sojojin Japan sun kai hare-hare a kan Pearl Harbor, da kuma sojojin Birtaniya a Malaya, Singapore, da Hong Kong, da sauransu, suna fara yakin duniya na biyu a cikin Pacific. A duk yankunan da Japan ta mamaye a lokacin yakin, an aikata laifuka da yawa a kan mazauna yankin, tare da tilasta wa mutane da yawa yin bautar jima'i. Bayan nasarar Allied a cikin shekaru hudu masu zuwa, wanda ya kai ga mamayewar Soviet na Manchuria da bama-bamai na atomatik na Hiroshima da Nagasaki a 1945, Japan ta amince da wani
mika wuya ba tare da wani sharadi ba. Yaƙin ya kashe Jafan mallaka da miliyoyin rayuka. Allies (wanda Amurka ke jagoranta) sun dawo da miliyoyin mazauna Japan daga tsoffin yankunansu da sansanonin soja a duk faɗin Asiya, suna kawar da daular Japan da tasirinsa a kan yankunan da ya ci nasara. Allies sun kira Kotun Soja ta Duniya don Gabas ta Tsakiya don gurfanar da shugabannin Japan don laifukan yaki.