Wokou, which translates to "Japanese pirates", were pirates who raided the coastlines of China and Korea from the 13th century to the 17th century. The wokou were made of various ethnicities of East Asian ancestry, which varied over time and raided the mainland from islands in the Sea of Japan and East China Sea. Wokou activity in Korea declined after the Treaty of Gyehae in 1443 but continued in Ming China and peaked during the Jiajing wokou raids in the mid-16th century. Chinese reprisals and strong clamp-downs on pirates by Japanese authorities saw the wokou disappear by the 17th century.

Imagawa Sadayo , also known as Imagawa Ryōshun , was a renowned Japanese poet and military commander who served as tandai ("constable") of Kyūshū under the Ashikaga bakufu from 1371 to 1395. His father, Imagawa Norikuni, had been a supporter of the first Ashikaga shōgun, Ashikaga Takauji, and for his services had been granted the position of constable of Suruga Province. This promotion increased the prestige of the Imagawa family considerably, and they remained an important family through to the Edo period.