An Yong-bok, who lived during the reign of King Sukjong of the Joseon dynasty, made two trips to Japan, the first of which was against his own will in 1693 when he was captured by the Japanese in Ulleungdo.
The 1693 kidnapping of An Yong-bok triggered the Ulleungdo Dispute between Korea and Japan. The kidnapping is significant because the jurisdictional status of Ulleungdo and Dokdo was confirmed in the course of the diplomatic negotiations that ensued.

Regarding An Yong-bok’s second trip to Japan in 1696, a record of An Yong-bok’s statement can be found in the Sukjong Sillok (Annals of King Sukjong’s Reign). It is recorded that An Yong-bok told the Japanese fishermen he encountered in Ulleungdo that “Matsushima is Jasando [Dokdo] which is Korean territory” and that he went over to Japan to lodge a protest against Japan’s encroachment on the Korean territories of Ulleungdo and Dokdo.

An Yong-bok’s journeys to Japan are recorded not only in Korean but also in Japanese documents, including Takeshima Kiji (Records of Takeshima), Takeshima Tokai Yurai Kinuki Gaki (Copy of Excerpts from Record of a Trip to Takeshima), Inpu Nenpyo (Chronology of Inaba Province), and Takeshimako (Notes on Takeshima).

Particularly noteworthy is a historical document discovered recently in 2005 in Japan entitled “Genroku Kyu Heishinen Chosenbune Chakugan Ikkan No Oboegaki” (Memorandum on the Arrival of a Boat from Joseon in 1696 – a report on An Yong-bok’s visit to the Oki Islands drafted by an official of the island). According to the report, An Yong-bok stated that Ulleungdo and Dokdo belonged to Gangwon-do, which corroborates the information in the Sukjong Sillok (Annals of King Sukjong’s Reign).