Japanese nationalists on Sunday landed on islands controlled by Tokyo but claimed by China, which knows them as Diaoyu, in the latest development in a long-running territorial row.
Here is a brief outline of the governments’ competing claims to the archipelago in the East China Sea.
Tokyo says its government began surveying the islands in 1885 and found them unoccupied with “no trace of having been under the control of China”.
On January 14 1895 the cabinet decided to erect a marker to formally incorporate the Senkaku Islands into Japanese territory, the foreign ministry says.
“Since then the Senkaku Islands have continuously remained as an integral part of the Nansei Shoto Islands which are the territory of Japan,” it says.
Tokyo says the isles were not included in territory Japan renounced under the San Francisco Peace Treaty, which officially ended World War II, and Beijing expressed no objection at the time to their exclusion.
China and Taiwan began claiming the islands after 1970, after the possibility emerged of energy reserves being found in the seabed nearby, Japan says.
China’s claims date back to the Ming Dynasty (1368-1644) when reference to the Diaoyu Islands appeared on maps and in a book during the reign of Yong Le (1403-1424), according to a report by the official news agency Xinhua.
A map published by Japan in the 1780s also appears to prove China’s right to the islands, the report said, adding they were undisputed until they were ceded to Japan -- along with Taiwan -- at the end of the 1894-5 Sino-Japanese war.
Xinhua said the islands wrongly remained under Japanese control at the end of World War II when Tokyo relinquished its claim over Taiwan and the Penghu islands.
Taiwan separately claims ownership of the islands.