Sō clan
At the end of the 16th century, the Bunroku-Keicho War broke off the relationship between Korea and Japan. However, the Tokugawa shogunate started trading again with Korea by concluding the Treaty of Giyu with the Sō clan of Tsushima Island in 1609, establishing a relationship of near equality through mutual visits of Korean messengers. Tsushinshi were sent from Korea to pay homage to a new shogun or to celebrate the birth of an heir to a shogun. Korean envoys were provided with the same role as an envoy to bring tributes to a Chinese emperor or was used for showing the prestige of Tokugawa shogunate and vis versa.