Records dating back to 930 indicate that Usanguk, a tributary state to the Goryeo Kingdom (918-1392) occupied the island in addition to neighboring Ulleungdo. Geographical records from the Sejong Sillok (1432), or the "Chronicle of King Sejong" of the Joseon Dynasty also mention the island as Usando, land that "in clear weather comes into view." Even today, during fair weather Dokdo is visible from Ulleungdo, which is a mere 87 kilometers from the easternmost territory of Korea's Exclusive Economic Zone (EEZ).

Official Korean sovereignty over Dokdo was finalized in 1696 when Joseon-period patriot Ahn Yong-bok received written confirmation from the Tokugawa Shogunate of Japan recognizing Korean jurisdiction over it. Imperial Japan officially declared Dokdo its territory in 1905 in the opening stages of its forced annexation of the entire Korean Peninsula. It was consistent with the principle of national independence that Korea later reclaimed sovereignty over the island in upon liberation from the Japanese colonial rule 1945.

Historically, Korea has been aware of Dokdo’s existence since the 6th century. Japan, on the other hand, had not known about Dokdo until the 17th century. There are also a number of Japanese historical records and old maps in which Japan itself acknowledges that Dokdo is not its territory.

From the standpoint of international law, the Korean Empire legally proclaimed Dokdo as its territory, stipulating in its Imperial Decree No. 41 (1900) that Dokdo is under the jurisdiction of Ulleungdo. Japan’s Shiname Prefecture later illegally incorporated Dokdo into its territory by issuing Notice No. 40 (1905).

“East Sea” is a geographical designation used by Koreans for over 2,000 years. Unfortunately, however, the use of “Sea of Japan” became widespread in the international community starting in and around the Japanese colonial period, and this erroneous usage persists to date. That is why we are trying to reclaim the correct geographical name “East Sea” for the waters of Dokdo.

Unequivocally, Dokdo in the East Sea is the rightful territory of the Republic of Korea, geographically, historically, and from the standpoint of international law.