1. Sovereignty: Legal and Historical Aspects


On January 14, 1895, the Japanese cabinet approved a decision to erect sovereignty markers on Uotsuri Island and Kuba Island and incorporate the islands into Japanese territory. Previously, government and private expeditions had landed on the Senkaku Islands and conducted surveys, and private citizens had developed the land, mainly for fishing activities. Because of this, and to regulate fishermen, the Japanese government found it necessary to place the islands under its sovereignty and administer them directly.

After the islands became part of Japanese territory, the government formally leased them to Koga Tatsushiro, who developed them for business with sites on Uotsuri Island and Kuba Island. During this period the government managed the islands, setting land numbers (chiban) for each island, recording the islands in land registries, sending administrative officials to visit them, and carrying out academic studies.

In 1922, the government formally incorporated Kumeakashima Island into Japanese territory, at the same time changing its name to Taisho Island. Then, in 1932 Uotsuri Island, Kuba Island, Minamikojima Island, and Kitakojima Island were sold to Koga Zenji, the son of Koga Tatsushiro and inheritor of his business.

After World War II, in Article 3 of the 1951 San Francisco Peace Treaty, the Nansei Islands, including the Ryukyu Islands, and within them, the Senkaku Islands, were placed under US administration. The United States oversaw and managed the islands, designating US army proving grounds on Kuba Island and Taisho Island, requiring payment of fixed property and other taxes from Koga Zenji to the US Civil Administration of the Ryukyu Islands, warning Taiwanese people who had entered illegally to dismantle wrecks, and putting up warning signs. On June 17, 1971, the Okinawa Reversion Agreement was signed. This came into effect on May 15, 1972, and sovereignty of Okinawa Prefecture, including the Senkaku Islands, returned to Japan.

As of this version, this website includes facts and figures from the Meiji era (1868-1912) to around the time that Okinawa was returned to Japanese administration.

*Click the links to go to the individual pages.

A. Before incorporation: from territorial intentions to incorporation measures

January 12 and 14, 1895Decision to Incorporate the Senkaku Islands Into Japanese Territory (Cabinet Decision to Construct Sovereignty Markers)Read ≫
1885Japanese Government Orders Okinawa Prefecture to Conduct the Senkaku Islands SurveyRead ≫
December 5, 1885Further Petition from Okinawa Prefecture and Postponement of Construction of Sovereignty MarkersRead ≫
January 13, 1890Petition to Incorporate the Senkaku Islands from the Yaeyama Islands GovernmentRead ≫
October 22, 1885Okinawa Representatives Sent on Izumo Maru to Survey Potential for DevelopmentRead ≫
November 2, 1893Renewed Petition by Okinawa Governor to Home and Foreign MinistersRead ≫
January 21, 1895Drawing Up of Markers Construction Draft DirectiveRead ≫
January 22 and February 2, 1895Sending of Markers Construction Draft DirectiveRead ≫
December 15 and 27, 1894, and January 11, 1895Drawing up of Cabinet Proposal and Home and Foreign Ministerial Consultation Regarding Construction of MarkersRead ≫
From 1859Oshiro Eiho Lands on the Senkaku IslandsRead ≫
October 9 and October 21, 1885Home Minister Asks Foreign Minister's Opinion Regarding Construction of Sovereignty MarkersRead ≫

B. Effective control after incorporation

From 1895Koga Makes Request and Is Granted 30 Year Lease Free of ChargeRead ≫
1904 and 1907Visits to the Senkaku Islands by Government OfficialsRead ≫
From 1926Change From Free Lease to Paid Lease for KogaRead ≫
July 1945Rescue of Ishigaki Residents After Their Evacuation Ship Came Under Machine-Gun Fire and Commemoration of This EventRead ≫
1932Sale of Uotsuri Island, Kuba Island, Minamikojima Island, and Kitakojima Island to KogaRead ≫
1922Kumeakashima Designated as Japanese Territory and Renamed TaishotoRead ≫
From 1939Surveys by Ministry of Agriculture and Forestry Resource Survey Team and Ishigakijima Weather StationRead ≫
March 5, 1896Division of Okinawa by Imperial EdictRead ≫
From 1884Development of the Senkaku Islands by Koga TatsushiroRead ≫

C. Legal status after World War II

1967–1968Active Response to Taiwanese Workers Dismantling Wrecks (Minamikojima Island)Read ≫
April 12, 1971The Senkaku Islands Included in Geographical Scope of Okinawa Reversion AgreementRead ≫
September 3, 1968Proposal from US Civil Administration to Install Signboards Warning Against Illegal EntryRead ≫
1953–1955The Senkaku Islands Mentioned in US Civil Administration DocumentsRead ≫
1952San Francisco Peace Treaty and Provisions of the Government of the Ryukyu Islands (US Civil Administration Ordinance No. 68)Read ≫
June 17, 1971Signing of the Okinawa Reversion TreatyRead ≫
December 26, 1969Prior Notification and Lease of Kuba Island to Be Used as US Military Bombardment and Shooting TargetRead ≫
From 1968Active Response to Taiwanese Workers Dismantling Wrecks (Kuba Island)Read ≫
1961Fixed Property Taxes and Taxation of Usage Fees for Military Firing RangeRead ≫
July 9–13, 1970Warning Signboards Installed on Five Senkaku IslandsRead ≫
1950The Senkaku Islands Included in US Occupation Government's Law Concerning the Establishment of the Archipelago GovernmentsRead ≫