How War of Resistance victory cemented China's South China Sea claim
2025-08-19 11:25:19 source：CGTN
August 19, 2025
Throughout history, the South China Sea has been a hub of open navigation, smooth trade, the exchange of technologies and the meeting of ideas. China, despite its geographic advantage, growing national strength and expanding military capabilities, has never used the South China Sea as a means to threaten the development of neighboring countries.
However, in the early 20th century, as Western powers doubled down on their encroachment on China and Southeast Asia, countries such as the UK, Germany, France and Japan began to cast covetous eyes on the Nansha Qundao. Around the time of World War II (WWII), Japan gradually occupied most of the islands and reefs that belonged to China in the South China Sea. These acts of aggression by foreign powers met with firm resistance from both the Chinese government and the Chinese people. As a result, some of these attempts at seizure ended in failure.
After the victory in the Chinese People's War of Resistance Against Japanese Aggression, China, based on international law and the outcomes of WWII, undertook a series of actions to reaffirm its sovereignty over the islands in the South China Sea, including formally taking over the islands, renaming them and erecting sovereignty markers. These steps provided a clear legal foundation for China's sovereign claims over these islands.
In November 1943, the leaders of China, the United States and the UK stated in the Cairo Declaration that "it is the purpose of the three Allies that Japan shall be stripped of all the islands in the Pacific which she has seized or occupied since the beginning of the World War I in 1914," and that all the territories Japan had stolen from China, such as Northeast China, Taiwan and the Penghu Islands, should be restored to China.
Subsequently, Article 8 of the Potsdam Proclamation issued on July 26, 1945, reaffirmed that "the terms of the Cairo Declaration shall be carried out" and that "Japanese sovereignty shall be limited to the islands of Honshu, Hokkaido, Kyushu, Shikoku and such minor islands as we determine."
It is worth noting that, back then, the international community, including countries surrounding the South China Sea, did not dispute China's sovereignty over the islands in the region. In fact, Chinese forces reclaimed the islands aboard naval vessels provided by the United States.
For example, Yongxing Island, which is now the seat of both the Sansha city government of Hainan Province and the Xisha District People's Government, was named after the U.S. Navy's patrol ship Yongxing. In 1946, the Kuomintang (KMT) government's vice commander, Yao Ruyu of the Yongxing led staff officer Zhang Junran aboard the ship and commanded the Zhongjian to recover the Xisha Qundao. This also indicates, indirectly, that the U.S. government at the time was both aware of and acquiescent to China's sovereignty over the South China Sea islands.
At the end of 1946, the then-Chinese government dispatched naval vessels to the Xisha Qundao and Nansha Qundao to formally conduct sovereignty restoration ceremonies, re-erect sovereignty markers and reclaim administrative authority over the islands. Zheng Ziyue, a professor in the Department of Geography at Northwest University, was commissioned by the then-Chinese government to join the expedition. He was tasked with delineating maritime boundaries in the South China Sea and standardizing the names of islands, reefs, rocks and shoals in the region.
Based on on-site surveys and mapping, Zheng completed a series of official maps under the auspices of the Ministry of the Interior of the KMT government, including the location map for the South China Sea Islands, detailed maps of the Xisha Qundao, Zhongsha Qundao and the Nansha Qundao, as well as individual maps of Taiping Island, Yongxing Island and Shidao Island. He also compiled a comparative table matching the islands' newly designated names with their historical ones.
In 1947, the Chinese government officially approved a revised list of 172 geographic names for the island groups and individual features in the South China Sea, including 102 in the Nansha Qundao. It also produced the Location Map for the South China Sea Islands, on which the dotted line is marked.
Shortly after the end of WWII, amid the deterioration of cross-Straits relations, the onset of the Cold War and growing confrontation between the two global blocs, the San Francisco Peace Treaty was signed to address Japan's postwar territorial arrangements and international status as a defeated country. Article 2, Paragraph 6 of the treaty's "Territory" section states that Japan would renounce all right, title and claim to the Nansha Qundao and the Xisha Qundao. However, the treaty did not specify to whom these territories would be returned.
In response, the People's Republic of China's government issued a formal statement on August 15, 1951, expressing opposition to the treaty's failure to address the question of restoring China's sovereignty over these islands, despite Japan's renunciation of claims. The statement reaffirmed that the islands in the South China Sea, including the Nansha Qundao, "have always been part of Chinese territory" and emphasized that, following Japan's surrender, "the then Chinese government had already taken full possession of these islands." It further declared that the sovereignty of the People's Republic of China over these territories "is in no way affected" by the terms of the treaty.
In fact, China's sovereignty over the South China Sea islands is well-established throughout history. Since ancient times, the Chinese people have lived and engaged in productive activities on the South China Sea islands and in the surrounding waters. Over the course of this long history of development and use, Chinese fishermen also formed a relatively stable system of naming the islands and features in the region.
Numerous foreign records have documented that for an extended period, only Chinese people were living and working in the Nansha Qundao. For example, the Japanese publication Island of Storms (1940) and Volume IV of Asiatic Pilot, issued in 1925 by the U.S. Navy Hydrographic Office, both record Chinese fishermen's activities in the Nansha Qundao.
Until the 20th century, China's sovereignty over the South China Sea islands was never challenged. It was not until the 1930s and 1940s that France and Japan successively used force to illegally occupy certain islands and reefs of China's Nansha Qundao. In response, the Chinese people rose in resistance, and the then-Chinese government took a series of measures to safeguard its sovereignty over the Nansha Qundao.
The Cairo Declaration and the Potsdam Proclamation are foundational legal instruments that shaped the postwar international order, particularly in relation to territorial arrangements in East Asia. These documents possess unquestionable legal force under international law.
In the context of the South China Sea, the territorial principles established by these postwar legal documents apply fully and without dispute. They explicitly stipulate that Japan must return all territories it had stolen from China. This is in line with a widely recognized principle of postwar justice: complete reckoning with Japanese aggression and restoring international fairness and justice.
During WWII, the islands and reefs in the South China Sea, including the Nansha Qundao, were unlawfully occupied by Japan. In accordance with the postwar legal principle of "returning stolen territory to its rightful owner," these islands were rightfully returned to China, the country to which they belonged prior to Japan's occupation.
China's assertion of sovereignty over the South China Sea islands, including the Nansha Qundao, is firmly grounded in international law. One of the clearest and most authoritative legal bases for China's claim stems directly from these legal documents that serve as cornerstones of the postwar international order and the principles they established. This marks not only a continuation of China's historically established sovereignty but also a concrete manifestation of the territorial arrangements prescribed by the postwar international legal order.
China bears the deep historical memory of its territorial sovereignty being violated. As a nation that has risen from such a painful past, China has never resorted to "bullying the weak with strength." At the same time, it will not allow any party to exploit their status as "small countries" to coerce China as a large country and replay that past trauma in the South China Sea.
China's sovereignty and rights in the South China Sea are rooted in its long-standing historical presence and solidified through the postwar international order forged through sacrifice and victory. China's position on the South China Sea is not only about safeguarding its own sovereignty, security, and development interests, but also concerns whether the principles of justice, the rule of law and the vision of peace, which were established in the aftermath of WWII, will continue to be respected.
In an era of peace, China's efforts to safeguard its sovereignty in the South China Sea while promoting the peaceful resolution of disputes are, fundamentally, a continuation of the spirit of contribution that China brought to the victory in the World Anti-Fascist War.
Ding Duo is the director of the Research Center for International and Regional Issues at the National Institute for South China Sea Studies.