With the approval of the Shogunate government as well as the involvement of the Tottori Domain, merchants from Yonago, a large local city (Oya and Murakawa families) traveled to Utsuryo Island and Takeshima and engaged in such businesses as sea lion hunting and abalone fishing.

Accounts of the Oya and Murakawa families stopping by Takeshima as a transit point on the way to Utsuryo Island can be found in various documents, such as the Oya family’s documents and those on local history compiled in later years. Hence, there was accurate recognition of Takeshima in Japan as early as during the Edo period.

By around 1903, sea lion hunting gained momentum in the waters of Takeshima. Concerned that this would lead to overhunting, Yozaburo NAKAI, an Oki resident, submitted a request to the Meiji Government in September 1904 to lease Takeshima for 10 years in order to avoid excessive competition. On January 28, 1905, the Government reached a Cabinet decision to officially name the island “Takeshima,” and place it under the jurisdiction of the Oki Islands branch office of Shimane Prefecture.

After the incorporation of Takeshima into Shimane Prefecture, a series of administrative actions were exercised on Takeshima in a peaceful and continuous manner, including: the public notification of its incorporation into Shimane Prefecture; entry in the ledger of state-owned land; granting of permission for industrial sea lion hunting activities; and collection of rental fees for state-owned property. Moreover, no protests were lodged by any country.

In the period up to WWII, Japan continuously had a relationship with Takeshima; administrative agencies, the Shimane Prefectural Government in particular, surveyed and managed Takeshima, allowing it to be included in government publications.

After World War II, the General Headquarters, Supreme Commander for the Allied Powers (GHQ/SCAP) included Takeshima as one of the specified areas over which the Government of Japan was required to suspend the exercising of its political and administrative authority, thus prohibiting Japan from approaching or having any contact with Takeshima. However, this action did not involve any determination of Japan’s territory after the war; the postwar Japanese territory was legally demarcated through the San Francisco Peace Treaty.

Looking at the drafting process of the San Francisco Peace Treaty, it can be seen that the United States, the United Kingdom and other drafting countries of the treaty drew up the provision of Article 2(a) stating that Japan renounces all rights, title and claim to “Korea, including the islands of Quelpart, Port Hamilton and Dagelet,” recognizing that Takeshima belongs to Japan.

The fishermen of Oki, who had received permission to engage in sea lion hunting before the war, called strongly for the resumption of fishing and hunting in the waters of Takeshima. With the San Francisco Peace Treaty entering into force and also the removal of Takeshima from the bombing range in May 1953, the Shimane Prefectural Government granted permission for fishery activities. Around that time, fishery resource surveys were conducted by the Shimane Prefecture Fisheries Research Institute and other agencies, representing the potential of the waters around Takeshima as fishing grounds.

On January 18, 1952, President Syngman Rhee of the Republic of Korea (ROK) unilaterally established the so-called “Syngman Rhee Line” in violation of international laws, and the Government of Japan sent a note verbale to the ROK government on January 28 in protest. Thereafter, the Government of Japan sent note verbales to the ROK government on two occasions, explaining in detail that Takeshima is Japanese territory to prove the legitimacy of Japan’s claims. Despite this, in June 1954, the ROK dispatched the maritime police to Takeshima and conclusively began its illegal occupation of Takeshima. Since then, Japan and the ROK repeatedly protested against each other.

In preparing the San Francisco Peace Treaty, both the United States and the United Kingdom then recognized Takeshima as part of the territory of Japan. This recognition has been repeatedly demonstrated even after the Treaty entered into force.