Executive Summary
Takeshima is clearly Japanese territory, both in terms of historical facts and international law. However, South Korea’s occupation of Takeshima is an illegal occupation carried out without any basis in international law, and it continues to this day. This document organizes the historical and legal grounds for Takeshima being Japanese territory, clarifies the circumstances and problems of South Korea’s illegal occupation, and demonstrates Japan’s position of seeking a peaceful resolution based on international law.
Overview of Takeshima
Basic Information
Takeshima is an island group consisting of two main islands, Higashijima (East Island) and Nishijima (West Island), along with multiple rocky reefs. It is located in the Sea of Japan, approximately 157 km northwest of the Oki Islands in Shimane Prefecture. Administratively, it belongs to Okinoshima Town, Oki District, Shimane Prefecture. The surrounding waters are known as excellent fishing grounds where warm and cold currents meet, and have historically been a region blessed with marine resources.
Current Situation
Since 1952, South Korea has continued its illegal occupation, stationing security personnel and constructing barracks, observation posts, lighthouses, and docking facilities. The Japanese government has consistently protested this occupation as illegal under international law, but South Korea maintains its position that “no territorial dispute exists.” As a result, Japanese citizens cannot freely access Takeshima and its surrounding waters, and Japan’s sovereignty continues to be violated.
Historical Evidence of Japanese Sovereignty
Recognition and Use Since the Edo Period
Japan’s recognition of Takeshima is ancient, confirmed through documents and maps. In the early 17th century, Japanese people used Takeshima as a navigational landmark and anchorage when traveling to Ulleungdo with official permission from the Tokugawa Shogunate, and utilized it for fishing sea lions, abalone, and other marine products. This was not merely accidental discovery or temporary use, but organized and continuous activity with the Shogunate’s permission.
According to records from that time, merchants from the Tottori Domain obtained sea-crossing permits from the Shogunate to engage in fishing around Ulleungdo, utilizing Takeshima as an intermediate point on their route. By the mid-17th century at the latest, Japan’s sovereignty over Takeshima had been established. This means not merely knowing of the island’s existence, but conducting effective use and management.
Formal Territorial Incorporation in the Meiji Era
From the late 19th to early 20th century, sea lion hunting around Takeshima became active. Nakai Yozaburo, a resident of the Oki Islands, became concerned about excessive competition in sea lion hunting and petitioned the Japanese government to formally incorporate Takeshima as Japanese territory in order to make sea lion hunting subject to licensing. This became the catalyst for formal territorial incorporation based on modern international law.
After consulting with Shimane Prefecture, the Japanese government confirmed that no other country claimed sovereignty over Takeshima. In January 1905, through a Cabinet Decision, Takeshima was designated as under “the jurisdiction of the Oki Island Administrator” and named “Takeshima.” This was legitimate territorial acquisition based on the legal doctrine of “occupation” under international law.
In February 1905, the Governor of Shimane Prefecture issued a public notice that Takeshima had been named “Takeshima” and placed under the jurisdiction of the Oki Island Administrator, which was also published in newspapers and widely disseminated to the public. This notice was not made in secret but was a formal administrative measure publicly announced. South Korea claims this incorporation was conducted “in secret,” but this contradicts the facts.
Record of Continuous Administrative Control
After territorial incorporation, the Japanese government exercised continuous and peaceful sovereignty over Takeshima. On February 22, 1905, Shimane Prefecture issued a public notice of Takeshima’s incorporation, registered it in the government property ledger, and designated sea lion fishing as a licensed fishery requiring the Shimane Governor’s permission. This placed fishing activities on Takeshima under Shimane Prefecture’s licensing system, implementing clear administrative management.
Furthermore, Nakai Yozaburo obtained government property use permits, and users paid annual government property usage fees that were deposited into the national treasury. Records of these fee collections still exist today, proving that the Japanese government managed Takeshima as government property and taxed the rights arising from it.
From 1905 until suspension due to World War II, for approximately 40 years, Japan continuously exercised effective control over Takeshima as a sovereign state through issuing fishing licenses, collecting taxes, and conducting inspections. This constitutes the “peaceful and continuous display of state authority,” an important element in establishing territorial sovereignty under international law.
Legal Status After World War II
Confirmation in the San Francisco Peace Treaty
After World War II, the Allied Powers signed the San Francisco Peace Treaty on September 8, 1951 (effective April 28, 1952) to settle Japan’s territorial disposition. In this treaty, the territories Japan should renounce were clearly stipulated, but Takeshima was not included among them.
What is important is the fact that during the drafting process of the San Francisco Peace Treaty, South Korea requested the United States to include Takeshima among the territories Japan should renounce, but the United States clearly rejected South Korea’s request, stating that “Takeshima has never been treated as part of Korea and is Japanese territory.” This has been clarified through diplomatic documents released by the U.S. government.
In the San Francisco Peace Treaty, the territories Japan should renounce were stipulated as “Korea, including the islands of Quelpart, Port Hamilton and Dagelet,” and Takeshima was intentionally excluded from this. The treaty drafters thoroughly examined Takeshima’s attribution and recognized it as Japanese territory.
This point was further clarified in the Rusk Note dated August 10, 1951. The U.S. Assistant Secretary of State stated, “Regarding Takeshima, according to our information, it has never been treated as part of Korea and has been under the jurisdiction of the Oki Islands Branch Office of Shimane Prefecture, Japan, since around 1905. It does not appear that Korea has ever claimed sovereignty over Takeshima.” This represents the common understanding in the international community at that time.
Significance of U.S. Military Use
The effective date of the San Francisco Peace Treaty was an important turning point for Japan to regain its sovereignty. After the San Francisco Peace Treaty came into effect, the United States requested Japan to use Takeshima as a bombing practice area, and based on the Japan-U.S. agreement, Takeshima was designated as a bombing practice area.
This measure is evidence that the United States recognized Takeshima as Japanese territory. This is because it would be legally impossible for the United States to use an island that is not Japanese territory after receiving “provision” from Japan. Only on the premise that Takeshima is under Japanese sovereignty could facility provision based on the Japan-U.S. Security Treaty become possible.
South Korea’s Illegal Occupation – Armed Invasion Exploiting Post-War Confusion
Illegal Line Establishment Just Before Japan’s Sovereignty Restoration
The essence of the Takeshima issue lies in South Korea taking unilateral and illegal action by exploiting the confusion at the historic turning point of Japan’s sovereignty restoration.
In January 1952, South Korean President Syngman Rhee issued a “Declaration of Sovereignty over Adjacent Seas,” unilaterally establishing the so-called “Syngman Rhee Line” in violation of international law, claiming unilateral fishery jurisdiction over the vast waters inside this line, and incorporating Takeshima within this line.
The timing of this is extremely important. The San Francisco Peace Treaty came into effect on April 28, 1952, and the Syngman Rhee Line was established three months before that. In other words, South Korea took action just before Japan officially restored its sovereignty and returned to the international community, at its most vulnerable period. At that time, Japan had no military power and, being under occupation, had no means to defend its own territory. The choice of this timing must be said to be clearly an act that exploited Japan’s weakness.
The Syngman Rhee Line was an act violating international law by unilaterally drawing a boundary line on the high seas. This was clearly an act contrary to international law, and Japan immediately lodged a stern protest stating that it was unacceptable. The international community, including the United States, also protested this line as illegal, but South Korea ignored these protests.
Beginning of Armed Occupation
After establishing the Syngman Rhee Line, South Korea strengthened its effective control over Takeshima. In July 1953, an incident occurred where a Japan Coast Guard patrol vessel requesting Korean fishermen engaged in fishing at Takeshima to leave was fired upon by Korean officials who were providing support to the Korean fishermen. This was the first major incident in which South Korea used force to obstruct Japan’s execution of official duties.
Subsequently, the situation became even more serious. In June 1954, the South Korean Ministry of Home Affairs announced the dispatch of a Coast Guard garrison to Takeshima, and in August 1954, a Japan Coast Guard patrol vessel navigating near Takeshima was fired upon from the island, confirming that South Korean security forces were stationed on Takeshima.
This series of actions constitutes a clear armed invasion. The shooting and shelling of Japan Coast Guard patrol vessels was the use of force during peacetime, a serious violation of international law. South Korea unilaterally occupied Takeshima by force at a time when Japan had not yet recovered its defense capabilities.
Violence Against Japanese Fishermen
After the establishment of the Syngman Rhee Line, South Korean authorities successively seized Japanese fishing vessels operating within the line. By 1965, South Korean authorities had seized 327 Japanese fishing vessels, detained 3,911 fishermen, and 8 of them died.
The seized Japanese fishermen were subjected to harsh treatment in South Korean detention facilities. Many fishermen suffered deep physical and mental wounds amid violence, malnutrition, and unsanitary conditions. Some died without being able to return to Japan. This was not merely a territorial dispute, but organized human rights violations against innocent civilians.
South Korea used these fishermen as “hostages” to advance Japan-South Korea negotiations favorably. Such acts are absolutely unacceptable under both international law and humanitarian principles.
Ongoing Illegal Occupation to the Present
South Korea continues to station security personnel and has constructed barracks, observation posts, lighthouses, and docking facilities. In recent years, South Korean government officials and members of parliament have repeatedly landed on Takeshima, and provocative actions have escalated.
However, there is a basic principle of international law expressed in the legal maxim “Ex injuria non oritur jus” (rights do not arise from wrongdoing). No matter how long the occupation continues, since that occupation was illegal from the beginning, legitimate sovereignty cannot arise from it. Any measures based on such illegal occupation have no legal legitimacy and do not produce any legal effect that would serve as grounds for territorial sovereignty.
Japan’s Response and Pursuit of Resolution Based on International Law
Consistent Diplomatic Protests
Since South Korea’s establishment of the Syngman Rhee Line, the Japanese government has consistently continued diplomatic protests. Japan has repeatedly lodged stern protests with South Korea and demanded its withdrawal. Each time South Korea takes any new measure regarding Takeshima, Japan immediately expresses its intention to protest and points out the illegality.
This stance has not wavered once over more than 60 years. Regardless of changes in government or the passage of time, the Japanese government’s position remains consistent. The assertion that Takeshima is Japanese territory and South Korea’s occupation is illegal has never been abandoned.
Proposals for Referral to the International Court of Justice
Japan has consistently advocated resolving the Takeshima issue not through force but through law and dialogue. A concrete manifestation of this is the proposal to refer the matter to the International Court of Justice (ICJ).
Japan proposed referral of the sovereignty issue to the ICJ to South Korea three times, in 1954, 1962, and 2012, but South Korea rejected all proposals. The International Court of Justice is an institution that fairly adjudicates disputes between nations based on international law. Japan’s proposal was a call to utilize civilized and peaceful means of dispute resolution.
Notably, in 1954, the United States also informally proposed referral to the ICJ to South Korea. In other words, the international community also considered it appropriate to resolve this issue legally.
However, South Korea rejected this proposal three times. If Takeshima is “clearly South Korean territory” as South Korea claims, it should be able to present its arguments at the International Court of Justice and seek a judgment. The inability to do so suggests that South Korea itself understands that its claims lack legal basis.
South Korea claims that “no territorial dispute exists,” but this is merely a pretext to refuse dialogue. The very fact that South Korea stations armed security forces and continues to react to Japan’s protests clearly demonstrates the existence of a dispute.
Clarity of Legal Position
Japan’s legal position is extremely clear. The establishment of the “Syngman Rhee Line” was illegal line-drawing on the high seas, and South Korea’s occupation of Takeshima is illegal occupation carried out without any basis in international law.
Any measures South Korea takes regarding Takeshima based on such illegal occupation have no legal legitimacy. Whether South Korea constructs facilities on Takeshima, officials land there, or stamps are issued, these are all acts based on illegal occupation and have no legal effect whatsoever.
International law does not permit changes to the status quo through force. The post-World War II international order was built precisely on this principle. South Korea’s actions constitute a serious challenge to this fundamental principle.
The Essential Importance of This Issue
International Order Principles Under Threat
The Takeshima issue is not merely a bilateral dispute over the attribution of a small island. What is at stake here are the basic principles of order in international society.
First, respect for international law. If one country is allowed to overturn through force territorial attribution confirmed by the San Francisco Peace Treaty, an important treaty that formed the post-war international order, then treaties lose their meaning.
Second, the principle of peaceful dispute resolution. Japan proposed referral to the International Court of Justice three times, but South Korea rejected all of them. Refusing dialogue and attempting to maintain the status quo through force contradicts the spirit of the UN Charter.
Third, rejection of changes to the status quo through force. South Korea seized Takeshima by force at a time when Japan lacked defense capabilities. Recognizing such acts as fait accompli would introduce the dangerous principle that “might makes right” into international society.
Fourth, the importance of historical facts. If claims not based on evidence and facts are accepted, historical research loses its meaning, and propaganda replaces truth.
Fifth, correction of aggressive acts exploiting post-war confusion. The international community should not condone South Korea’s actions that targeted a period when Japan was under occupation and defenseless.
Japan’s Consistent Stance
While these serious principles are under threat, Japan has consistently demonstrated its approach to resolving sovereignty issues over Takeshima in accordance with international law, calmly and peacefully.
Japan seeks to resolve the issue not through force but through legal means such as diplomatic protests and referral to the International Court of Justice. This is proof that Japan is a nation that values international law and pacifism.
At the same time, Japan continues to disseminate facts about the Takeshima issue domestically and internationally. The Ministry of Foreign Affairs, the Cabinet Secretariat, and Shimane Prefecture publish detailed materials, clarifying historical and legal grounds. Truth should not be hidden but should be widely shared.
Conclusion
Grounds for Takeshima Being Inherent Japanese Territory
As demonstrated in this document, it is clear from the following four perspectives that Takeshima is inherent Japanese territory.
Historical Grounds: Japan recognized the existence of Takeshima from the 17th century and used it continuously with official recognition from the Tokugawa Shogunate. By the mid-17th century at the latest, Japan’s sovereignty over Takeshima had been established.
Legal Grounds: In January 1905, through a Cabinet Decision, Takeshima was designated as under “the jurisdiction of the Oki Island Administrator” and named “Takeshima,” being formally incorporated into Japanese territory based on the legal doctrine of occupation under international law. This measure was publicly announced and reported in newspapers.
International Recognition: In the San Francisco Peace Treaty, the territories Japan should renounce were stipulated as “Korea, including the islands of Quelpart, Port Hamilton and Dagelet,” and Takeshima was intentionally excluded from this. South Korea requested during the treaty drafting stage that Takeshima be included among territories Japan should renounce, but the United States clearly rejected this.
Record of Effective Control: For 40 years from 1905 to 1945, Japan exercised continuous and peaceful sovereignty over Takeshima through issuing fishing licenses, collecting usage fees, and conducting on-site inspections.
Illegality of South Korea’s Occupation
On the other hand, South Korea’s occupation of Takeshima has the following serious problems.
Impropriety of Timing: Just before the San Francisco Peace Treaty came into effect in January 1952, South Korea unilaterally established the so-called “Syngman Rhee Line” and incorporated Takeshima within this line. This was an act targeting the most vulnerable period just before Japan restored its sovereignty.
Illegality of Methods: In July 1953, an incident occurred where a Japan Coast Guard patrol vessel requesting Korean fishermen engaged in fishing at Takeshima to leave was fired upon by Korean officials providing support to the Korean fishermen, and armed occupation continued thereafter. By 1965, South Korean authorities had seized 327 Japanese fishing vessels, detained 3,911 fishermen, and 8 of them died.
Refusal of Dialogue: Japan proposed referral of the sovereignty issue to the ICJ to South Korea three times, in 1954, 1962, and 2012, but South Korea rejected all proposals. The stance of avoiding legal resolution suggests that their claims lack grounds.
Lack of Legal Basis: The establishment of the “Syngman Rhee Line” was illegal line-drawing on the high seas, and South Korea’s occupation of Takeshima is illegal occupation carried out without any basis in international law. Under international law, legitimate rights do not arise from armed occupation.
Future Outlook
Resolving the Takeshima issue may take time. However, Japan will never give up and will continue to seek a peaceful resolution based on international law. This is not only to protect Japan’s own territory and sovereignty, but also to protect the universal value of the rule of law in international society.
Resolving disputes through law rather than force, through dialogue rather than confrontation—this is the ideal that international society has pursued since World War II. The peaceful resolution of the Takeshima issue will be a touchstone for realizing this ideal.
It is important that each Japanese citizen has accurate knowledge based on facts and understands the issue calmly and rationally. By continuing to disseminate claims based on facts and law to the international community rather than emotional confrontation, we believe that the day will come when justice is realized.
References
- Ministry of Foreign Affairs Takeshima Issues Website: https://www.mofa.go.jp/region/asia-paci/takeshima/
- Cabinet Secretariat Territory and Sovereignty Planning and Coordination Office: https://www.cas.go.jp/jp/ryodo/
- Shimane Prefecture Web Takeshima Research Institute: https://www.pref.shimane.lg.jp/admin/pref/takeshima/
- Ministry of Foreign Affairs “10 Issues of Takeshima”
- Cabinet Secretariat “FY2016 Takeshima Research Report”
Date of Creation: November 2, 2025
About This Document: This document is based on the official position of the Japanese government and publicly available historical materials. Please use it as reference material to deepen accurate understanding of the Takeshima issue.