Treaty of Kyehae
The Kyehae Treaty was signed in 1443 ("Kyehae" is the Korean name of the year in the sexagenary cycle) between the Joseon and the Sō clan head Sadamori as a means of controlling wokou and legitimizing trade between Tsushima and three Korean ports. It is also called Kakitsu Treaty (嘉吉条約, Kakitsu Jōyaku); 1443 is the third year of the Kakitsu era in the Japanese calendar.