In 1402, the Japanese shogun Ashikaga Yoshimitsu (despite not being the Emperor of Japan) was conferred the title of "King of Japan" by the Chinese emperor and through this title had similarly accepted a position in the imperial tributary system as of 1404. This relationship ended in 1408 when Japan, unlike Korea, chose to end its recognition of China's regional hegemony and cancel any further tribute missions. Membership in the tributary system was a prerequisite for any economic exchange with China. In exiting the system, Japan relinquished its trade relationship with China.

By the last decade of the 16th century, Toyotomi Hideyoshi, the most preeminent daimyō, had unified all of Japan in a brief period of peace. Since he came to hold power in the absence of a legitimate successor of the Minamoto lineage necessary for the imperial shōgun commission, he sought military power to legitimize his rule and to decrease his dependence on the imperial family. It is also suggested that Hideyoshi planned an invasion of China to fulfill the dreams of his late lord, Oda Nobunaga, and to mitigate the possible threat of civil disorder or rebellion posed by the large number of now-idle samurai and soldiers in unified Japan. It is also possible that Hideyoshi might have set a more realistic goal of subjugating the smaller neighbouring states (the Ryukyu Islands, Taiwan, and Korea) and treating the larger or more distant countries as trading partners, because throughout the invasion of Korea, Hideyoshi sought for legal tally trade with China.

By seeking to invade China, Hideyoshi was in effect claiming for Japan the role traditionally played by China in East Asia as the center of the East Asian international order. He rallied support in Japan as a man of relatively humble origins who owed his position to his military might. Finally, during the 1540s–1550s, the wakō had staged a series of samurai raids into Korea, some of which were so large as to be "mini-invasions". Hideyoshi mistakenly thought his enemies were weak.