East China Sea timeline
April 10, 2013
1945
July - In the Potsdam Declaration, the US, UK and China agree on the terms of a Japanese surrender. It is agreed that Japan must return all the territories it had occupied in China (such as Manchuria, Taiwan and the Pescadores Islands) after the Allied victory. The Senkaku Islands are not specifically mentioned.
1951
September - The Treaty of San Francisco, which officially ends the occupation of Japan by the victorious powers and returns sovereignty to Japan, does not mention the Senkaku Islands. The People's Republic of China, the Soviet Union and India refuse to sign the document.
Like Okinawa, the Senkaku Islands are initially administered in trust by the US. The United States pays rent to a private owner, as it uses the islands for target practice for bombers. This is an implicit US recognition of Japanese sovereignty over the islands.
1969
May - Okinawa prefecture erects a marker on the main island of the Senkaku group to emphasize Japan's territorial claims. Neither the People's Republic of China nor the Republic of China (Taiwan) protests.
Both Chinas only lodge claims when Japanese scientists discover an underwater oil field in the vicinity of the islands.
1972
Washington returns Okinawa and the southwestern islands, including the Senkaku Islands, to Japan. Since the Nixon administration is also negotiating with China at this time, the US is noncommittal on the status of the islands, leaving the question of ownership open.
1978
In negotiations on a peace treaty between Japan and China, both sides agree, as in 1972, to set aside the question of the islands.
April - Between 80 and 140 partly armed Chinese fishing boats enter the disputed waters of the Senkaku Islands. The Chinese fishermen display posters that express a claim to the islands.
1996
China and Japan join the United Nations Convention on the Law of the Sea (UNCLOS).
Japan's nationalist youth organization builds a lighthouse on one of the disputed Senkaku Islands. A group of Chinese people departs Hong Kong to tear it down. When the captain of the ship reverses course because of an approaching storm, some activists jump overboard. A young man drowns and is the first "martyr" of the island dispute.
2004
January - Japanese security forces fire water cannon on Chinese fishermen near the Senkaku Islands, injuring one.
2005
September - A Chinese warship is discovered near a disputed gas field.
A vessel of the Japan Coast Guard finds two Chinese patrol boats that have spent more than nine hours in Japanese waters.
At the controversial Chunxiao gas field northeast of the Senkaku Islands, Japanese planes spot five Chinese vessels, among which is a destroyer.
2006
October - A submarine of the People's Liberation Army of China pursues the US aircraft carrier Kitty Hawk in the East China Sea.
2010
April - Ten Chinese warships carry out a naval exercise to ward off submarines in the Strait of Miyako, northeast of the Senkaku Islands.
September - A Chinese fishing boat rams a Japan Coast Guard boat.
2011
March - A helicopter of the Chinese fishery authorities buzzes and obstructs a Japanese destroyer near a disputed gas field.
August - Chinese fishery patrol boats penetrate the 12-nautical-mile zone surrounding an island in the Senkaku group claimed by Japan.
November - The Japan Coast Guard arrests a Chinese fishing boat captain after a pursuit in the Goto Islands, south of the main Japanese island Kyushu.
2012
March - The Japanese Parliament gives names to 39 previously nameless islands in the Senkaku group and adjacent islands. The People's Republic of China responds promptly with its own names and descriptions for a total of 70 islands in the region. Taiwan also rejects Japan's naming.
April - It becomes known that conservative hard-line Tokyo Governor Shintaro Ishihara is negotiating the purchase of eight of the Senkaku Islands with their private Japanese owner.
September - The Japanese government buys three of the Senkaku Islands also claimed by China and Taiwan from their Japanese owner. It wants to forestall Ishihara's initiative and defuse the affair. Nevertheless, the move results in massive protests in China.
Dozens of Taiwanese fishermen and coast guard vessels approach the Senkaku Islands in a convoy. The Japan Coast Guard uses water cannon to try to stop the fleet. The Taiwanese fleet ultimately turns around.
December - A Chinese surveillance aircraft enters the airspace over the Senkaku Islands. According to Japanese statements, this is the first such incident since 1958. Japan sends eight F-15 fighters.
2013
January - Multiple Chinese aircraft penetrate the airspace over the Senkaku Islands.
February - Japan lodges a protest because a Chinese frigate has allegedly locked its fire control radar onto a ship of the Japanese Maritime Self-Defense Force. China denies the allegations.