Japan unilaterally annexes five islands and three barren rock groups in the East China Sea, calls them "Senkaku." China's Qing Dynasty later cedes Taiwan and adjacent islands to Japan under the Treaty of Shimonoseki, ending the First Sino-Japanese War.  Senkaku Islands are not included in the treaty.
Japan's government leases four of the islands, known in Japanese as Uotsuri, Minami, Kita and Kuba, to Tatsushiro Koga. 
Japan surrenders, ending World War II, and returns Taiwan and adjacent islands to China in accordance with the Cairo Proclamation and Potsdam Declaration. The U.S. military takes control of the Senkaku Islands. 
U.N. report says studies suggest the presence of large oil reserves in the waters of the Senkaku chain. 
Taiwan, China, officially claim sovereignty over the islands, calling them "Diaoyu."  
Japan regains control of Okinawa and the Senkaku/Diaoyu islands from the United States.  Tokyo agrees to let the U.S. military use Kuba and Taisho as firing ranges for an "indefinite" period.  Japan's defense ministry begins renting Kuba from its owners to ensure U.S. access to the island. Zenji Koga begins the process of selling Kuba, Uotsuri, Minami and Kita to the Kurihara family.  Sale completed in 1988. 
September: Japanese coast guard ships collide with a Chinese trawler as they try to chase it from the waters around the islands.  Japanese authorities detain the Chinese captain for two weeks, upsetting China, which responds by suspending political and cultural exchanges and stopping rare earth exports to Japan. 
July: Japanese Prime Minister Yoshihiko Noda says the central government is in talks to buy the islands from the Kurihara family. 
August 15: 14 pro-China activists sail to the islands to assert Chinese sovereignty claims.  Five swim ashore before the Japanese coast guard detains all the activists and deports them. 
August 19: Japanese nationalists land on Uotsuri to assert Japan's sovereignty claim, ignoring Tokyo's warning that the landing is unauthorized.