The Joseon Tongsinsa were missions sent to Japan by the Great Joseon, the dynastic kingdom of Korea before it was replaced by the Korean Empire in 1897.
Japan’s Edo period (1603-1867) witnessed the heyday of such Korean-Japanese diplomatic exchanges. The Joseon Dynasty intended to enhance its communication with Japan, while Japan wanted to mitigate problems resulting from its seclusion policy by trading with the Joseon.
At that time, Japan had not yet become a sea power, despite its status as an island nation. Taiwan experienced a similar situation during the Manchu Qing Dynasty (1644-1912).