Nine years ago, the arbitral tribunal in the South China Sea arbitration unilaterally issued a so-called ruling, attempting to deny China's territorial sovereignty and maritime rights in the region. At the time, the Chinese government rejected the award, maintaining that disputes should be resolved through bilateral negotiations.

The Chinese Foreign Ministry said the award "is null and void and has no binding force." It accused the Philippines of "bad faith," saying that the aim was not to resolve the dispute nor to maintain peace and stability, but simply to deny China's territorial sovereignty and maritime rights and interests.

Over the past decade, China has frequently faced external criticism for alleged "expansion" or "coercion" in the South China Sea. However, experts have noted that China's claims to sovereignty and maritime rights in the region have been consistent and continuous since 1947. 

Since the late 1990s, China's policy toward managing disputes in the South China Sea has remained unchanged – setting aside disputes and maintaining the status quo. Moreover, there is plenty of evidence showing that the Nansha Islands and adjacent waters are Chinese territory.

China's historic rights in the South China Sea

China's sovereignty and historic rights in the South China Sea are based on its long-term history of management and administration of the islands in the sea and the adjacent waters. They are also consistent with international law, including the United Nations Convention on the Law of the Sea.

The Chinese have long engaged in fishing and other productive activities in the South China Sea, which is an important waterway for Chinese ships. Since the Han Dynasty (202 BC - AD 220), they began to make use of the resources of the sea, passing through it. These practices constitute the basic facts of China's long-term administration and passage in the South China Sea.

China has sovereignty over four archipelagos in the South China Sea, namely, the Xisha, Nansha, Zhongsha and Dongsha islands, which are indicated by the dash lines on the map drawn in 1947.

During World War II, Japan occupied part of the Nansha Islands, but the 1943 Cairo Declaration and the 1945 Potsdam Declaration affirmed that territories taken by Japan, including those stolen from China, should be returned. Following Japan's defeat, the Chinese Nationalist government in 1946 reasserted control by sending warships to the area, establishing a base on Taiping Island, and renaming 159 islands and reefs. In 1947, China officially released a map delineating its claims with an eleven-dash line, which was later reduced to a nine-dash line. For a long time afterwards, the U.S. made no objections whatsoever. 

The sovereignty has also been recognized by other countries. For a long time after World War II, Vietnam, the Philippines and other neighboring countries did not object to China's sovereignty over the South China Sea islands and the nine-dash line. Many other countries and international organizations also recognized or acquiesced to it.

This is supported by a large number of foreign official documents and publications, as well as government archives. For example, from February 1957 to February 1961 the U.S. government made multiple application requests to the Taiwan authorities to allow the U.S. Air Force based in the Philippines to conduct nautical chart measurement and meteorological surveys in the vicinity of Huangyan Island and the Nansha Islands, obviously acknowledging China's sovereignty over these islands through the role of the Taiwan authorities.

Such acknowledgment was confirmed in books and maps published around this time such as Columbia Lippincott Gazetteer of the World (1961), Worldmark Encyclopedia of the Nations (1963) and Constitutions of the Countries of the World (1971), all of which clearly state that the Nansha Islands belong to China.

The nine-dash line

The nine-dash line, a heritage, is frequently questioned and attacked by the Philippines. In China, the drawing of dotted lines in the South China Sea began in the early 20th century. At that time, the maps compiled by private individuals first used dotted or continuous lines to show China's territory scope in the sea, said Hou Yi, the director at the China Marine History Research Office in the Institute of Chinese Borderland Studies, Chinese Academy of Social Sciences. 

In the 1930s, the government of the Republic of China began to standardize and manage map publishing. They established the Land and Waters Map Review Committee to examine the maps. In January 1935, the committee published the Map of Islands in the South China Sea, standardizing the names of 132 islands, reefs, sands and beaches. This was the first case of the Chinese government officially mapping the South China Sea islands in modern history.

After World War II, in accordance with the Cairo Declaration, the Potsdam Proclamation and other international legal documents, China resumed the exercise of sovereignty of islands in the South China Sea. In February 1948, the Interior Ministry of the Republic of China publicly issued the Location Map of South China Sea Islands. It was the first time that the Chinese government drew a U-shaped line in the South China Sea on an officially published map, demonstrating to the international community its sovereignty over the sea.

After 1949, the government of the People's Republic of China inherited this line and made appropriate adjustments to make it the nine-dash line we know today.

All official maps published by China after 1949 show this line, which clearly defines China's territorial sovereignty over the South China Sea islands within the line and its historic rights in the waters within the line.