The Diaoyu Islands, 222 kilometers northeast of China's Taiwan province, have been China's territory since ancient times. All records, whether contained in books and academic research or on old maps, have proved China's undeniable sovereignty over these islands.

1. The name Diaoyutai Island appeared in 1403 in the Chinese book Voyage with the Tail Wind.

2. A recently discovered book written during the Qing Dynasty (1644-1912) called Record of Ocean Nation again proved the islands have always been part of China. The islands have not been terra nullius ("land belonging to no one") at least since China's Ming Dynasty (1368-1644), which established a maritime defense zone that included the islets.

3. On a map published by Japan between 1783 and 1785, the islands were marked within China's borderlines.

4. Kiyoshi Inoue, a renowned Japanese historian, confirmed in his book The Diaoyu Islands and its Adjacent Islands that historical facts as early as the 16th century attest that the Diaoyu Islands, in the East China Sea between China and Japan, have been an intrinsic part of China's territory.

"It is a well-known fact that the Diaoyu Islands have been part of China's territory since the Ming Dynasty," he wrote in the third chapter of his book. His viewpoint was based on documents such as sea charts, logbooks and exploration records about South China, the Taiwan region and the Ryukyu Islands found in the library of the British Admiralty Board, as well as many Japanese historical records.

5. The islands were ceded to Japan after China lost the Sino-Japanese War of 1894-95 and signed the Treaty of Shimonoseki. But the Cairo Declaration in 1943 stipulated that Japan should return all of China's territories that it occupied, including these islands.

These provisions were later reinforced in the Potsdam Proclamation in 1945. In the same year, Japan announced its unconditional surrender, accepting the proclamation in its entirety. In accepting the proclamation, Japan obviously agreed to give up all territories it took from China, including the islands.

6. Japan cited a bilateral agreement signed with the United States in 1971, claiming the US "reverted" administrative rights of the islands to it under that document.

The government of the People's Republic of China has long maintained that it is illegal for the US to have unilaterally exercised "administrative rights" over the Diaoyu Islands and other islands after World War II. China never accepted the San Francisco Treaty of 1951, which excluded the Chinese government.

Japan's attempt to use the 1971 US-Japan agreement as a legal basis for its claim to the islands is also absurd because an issue involving China's territory cannot be solved by any agreement between two foreign countries.