A cikin 1402, shogun na Japan Ashikaga Yoshimitsu (duk da cewa ba Sarkin Japan ba) ya sami lakabin "Sarkin
Japan " daga sarkin kasar Sin kuma ta hanyar wannan lakabi ya karbi matsayi a cikin tsarin mulkin mallaka kamar na 1404. dangantaka ta ƙare a shekara ta 1408, lokacin da Japan, ba kamar
Koriya ba, ta zaɓi kawo karshen amincewa da mulkin yankin
China , da kuma soke duk wani karin haraji.Kasancewa cikin tsarin karba-karba ya kasance wani sharadi na kowane musayar tattalin arziki da kasar Sin.A yayin ficewa daga tsarin, Japan ta yi watsi da huldar kasuwanci da kasar Sin.A cikin shekaru goma na ƙarshe na karni na 16, Toyotomi Hideyoshi, mafi girma daimō, ya haɗa dukan Japan a cikin ɗan gajeren lokaci na zaman lafiya.Tun da ya zo ya rike madafun iko ba tare da wani halastaccen magajin zuriyar Minamoto da ake bukata ga hukumar mulkin shōgun ba, ya nemi ikon soja don ya halasta mulkinsa kuma ya rage dogaro ga dangin sarki.Har ila yau, an ba da shawarar cewa Hideyoshi ya shirya mamaye kasar Sin don cika mafarkin ubangijinsa marigayi,
Oda Nobunaga , da kuma magance yiwuwar barazanar rikice-rikicen jama'a ko tawaye da yawancin samurai da sojoji suka yi a Japan.Har ila yau, yana yiwuwa Hideyoshi ya kafa wata manufa mai ma'ana ta murkushe kananan kasashe makwabta (tsibirin Ryukyu,
Taiwan , da Koriya) da kuma kula da manyan ko fiye da kasashe masu nisa a matsayin abokan ciniki, saboda a duk lokacin da aka mamaye Koriya, Hideyoshi ya nema. don yin kasuwanci tare da China bisa doka.Ta hanyar neman mamaye kasar Sin, Hideyoshi yana da'awar Japan rawar da kasar Sin ta saba takawa a gabashin Asiya a matsayin cibiyar tsarin kasashen gabashin Asiya.Ya ba da goyon baya a Japan a matsayinsa na mutum mai ƙanƙan da kai wanda ke bin matsayinsa na ƙarfin soja.A ƙarshe, a cikin 1540s-1550s, wakō ya shirya jerin hare-haren samurai zuwa Koriya, wasu daga cikinsu sun yi girma har ya zama "ƙananan mamayewa".Hideyoshi yayi kuskure yayi tunanin makiyansa basu da karfi.