Japan–Korea Treaty of 1876 opens Korean ports

Background. Prior to 1876, Joseon maintained diplomatic relations primarily with China and Japan, with trade limited to designated border locations and the waegwan in Pusan. Western vessels began appearing in Korean waters in the early 19th century, but the Korean government remained wary. The Un'yō incident in 1875, where a Japanese warship surveyed coastal waters and engaged Korean fortifications, set the stage for negotiations.

Negotiations. Following the 1875 incident, debates within the Japanese government led to a mission to settle the matter. The chief negotiators were Kuroda Kiyotaka and Shin Heon. The treaty granted Japanese people rights such as extraterritoriality, permitted surveying operations, and allowed residence and trade in open ports. The treaty was named for Ganghwa Island, a site of previous violent confrontations.

Terms. The treaty ended Joseon's status as a tributary state of the Qing dynasty. It opened three ports to Japanese trade, specifically Busan, Incheon, and Wonsan. Article 5 authorized the search for two more suitable seaports in various provinces for opening in October 1877. The treaty also established protocols for diplomatic interactions between the Ministry of Rites and the Foreign Office.