4. Japan's illegal occupation of the Diaoyu Islands
Tatsushiro Koga, a Japanese national, explored the Diaoyu Islands in 1884 and claimed that he found the islands to be terra nullius. From 1885 to 1893, the Okinawa Prefecture requested permission thrice from the Japanese government to place the Diaoyu Islands under its jurisdiction and put up boundary markers. The Japanese government rejected the requests fearing reprisals from the Qing government. In January 1895, as the Qing Dynasty’s defeat in the First Sino-Japanese War was all but certain, the Japanese government illegally occupied the Diaoyu Islands and "incorporated" them into Okinawa Prefecture. In April the same year, by signing the unequal Treaty of Shimorioseki, Japan forced the Qing Dynasty to cede "the island of Formosa (Taiwan), together with all islands appertaining or belonging to the said island of Formosa" to Japan. In 1900, the Japanese government renamed the Diaoyu Islands the "Senkaku Islands".
5. Backroom deals between Japan and the United States and protest statements by China
The Treaty of Peace with Japan (commonly known as the Treaty of San Francisco) was signed by Japan, the United States and other countries on 8 September 1951, agreeing to place the southwestern islands south of the 29th parallel of north latitude under its trusteeship system, with the United States as the sole administering authority. In December 1953, the Ryukyu government under the United States trusteeship issued a proclamation defining its geographical boundary lines, with the Diaoyu Islands being clearly included.
On 18 September 1951, Zhou Enlai, then Chinese Premier and Foreign Minister, made a solemn statement on behalf of the Chinese government that the Treaty of Peace with Japan signed in San Francisco was illega1 and invalid and could under no circumstances be recognized by the central government of China as China was excluded from its preparation, formulation and signing.
On 17 June 1971, Japan and the United States signed the Okinawa Reversion Agreement, which provided that all and any powers of administration over the Ryukyu Islands would be returned to Japan on 15 May 1972. The agreement included the Diaoyu Island and its adjacent islets in the territories and territorial waters to be reversed to Japan. On the same day the agreement was signed, the spokesman of the U.S. State Department stated that the