Since the 1970s China began making their assertions that the Senkaku Islands have been the territory of China from ancient times, which was after the possibility of oil reserves in the area surrounding the Senkaku Islands had been indicated.
While China argues that China was first in the history to discover the Senkaku Islands, because there are descriptions of the Senkaku Islands in Chinese ancient documents and maps, and that the Senkaku Islands are located close to China geographically, there is no evidence that China had discovered the islands before other countries discovered. In any case, the mere discovery of an island or geographical proximity does not constitute valid basis for the territorial sovereignty.
Under international law, continuous and peaceful display of sovereignty with a clear intention of possessing territory is deemed necessary for gaining territorial title. However, there is no evidence from China that the country ever had such effective control over the Senkaku Islands.