An Encyclopaedia on Chinese History, Literature and Art

The South China Sea Conflict

Sep 8, 2017 © Ulrich Theobald

China's newest official names for the Paracel Islands (traditionally called Xisha Qundao 西沙群島), Xuande Qundao 宣德群島 (Amphitrite Group) and Yongle Qundao 永樂群島 (Crescent Group), express that the country's claims date back to history, namely the early Ming period 明 (1368-1644), when the court of the Yongle (r. 1402-1424) and the Xuande (r. 1425-1435) emperors sent several diplomatic naval missions to Southeast Asia and beyond. According to international law and with a neutral interpretation of historical sources, such claims are without substance. Dynastic China used the southern sea as a vague maritime frontier, a buffer zone not expressing any territorial rights or claims. While references to the Paracel Islands can be attested in historiographical sources, such to the Spratly Islands (Nansha Qundao 南沙群島) cannot be substantiated.

Map 1. The South China Sea Conflict
The map shows the Pratas (Dongsha), Paracel (Xisha, Zhongsha) and Spratley (Nansha) Islands, with the names of various isles, shoals, reefs, banks, and atolls, the Nine-Dashes Line surrounding sea territory claimed by China, the territories claimed by other states involved, as well as installations (airfields, defense structures, helipads and radar posts) of the PR China and Taiwan (ROC). Installations by other claimants (Vietnam in the southwestern and central and the Philippines in the northeastern part of the Spratly archipelago) are not shown. Click to enlarge.

The origin of Chinese claims

The earliest European map on the area, published by the British Admiralty, dates from 1805. The Spratly Islands are named after Captain Richard Spratly (1802–1870), who "discovered" the archipelago in 1843. The name of the Paracel Islands, well known to earlier navigators because they were located close to the usually frequented western route, goes back to a Portuguese word for "shoal".

The first Chinese statement on the South China Sea issue was a reaction to Japanese economic activities on the Pratas Islands (Dongsha Qundao 東沙群島). The cartographer Hu Jinjie 胡晉接 (1870-1934) could convince Japan to accept Chinese sovereignty over the Pratas, but he included in his atlas from 1914 (Zhonghua minguo dili xin tu 中華民國地理新圖) also the Paracel Islands (including Zhongsha Qundao 中沙群島, the Macclesfield Bank). French intrusion in the Spratly archipelago led to the foundation of a Land and Water Maps Inspection Committee (XXX) in 1933 which identified the Spratly Archipelago as Chinese and gave each of the islands, rocks and atolls Chinese names. The James Shoal (Zengmu'an Sha 曾母暗沙) was at that time not included into the islands claimed by China, but the spot became the southernmost tip of the U-shaped Chinese-claimed area in 1935. The line drawn on the Committee's maps were supposed median lines between the coastline of the neighbouring contries and the islands in question.

In February 1948, the fundamental map Nanhai zhudao weizhi tu 南海諸島位置圖 was published by the Geography Department of the Ministry of Internal Affairs (Zhonghua minguo neizhengbu 中華民國內政部) of the Republic of China as appendix to the "Administrative Division Map of the Republic of China" (Zhonghua minguo xingzheng quyu tu 中華民國行政區域圖). In this map, maritime border line was executed in eleven dashes (shiyi duan xian 十一段線). For this reason the late Republican map is also known as the eleven-dashes map. It expresses Chinese claims over the whole area between the coast of Guangdong and the James Shoal, including the Paracel and Spratly Islands.

The People's Republic inherited the claims, but reduced the dashes to nine (jiu duan xian 九段線), as a concession to Vietnam in the area of the Gulf of Tonkin, where exact borders were defined in 2000.

It is unclear whether this map (as it is perpetuated on all maps showing the PRC and the Republic of China/Taiwan) claims only the islands in the area or also the see territory around. In a conservative interpretation, the maps just show the traditional maritime boundary as a buffer zone between China proper and other states. Yet the most extreme form, the U-shaped line expresses China's exclusive sovereignty over all islands, the waters, and all activities on and in them (fishing, mineral extraction, passage).

The nine-dashes line was first used in official communication in May 2009, when China presented a diplomatic note to the UN Commission on the Limits of the Continental Shelf (UNCLOS) in protest against Vietnamese and Philippine claims of the Spratly Islands by expanding the line of the continental shelf. Yet China is still working at a legal explanation of the U-shaped line.

In May 1996, China declared strait baselines around the Paracel Islands which is actually not possible because the islands are not directly attached to an archipelago (China is not an archipelago), and the ratio of water to land far surpassed the quota allowed for such a case (Art. 46-47 UNCLOS). The area included in strait baselines counts as exclusive territory of an archipelago or uneven coastlines.

Claims by neighbouring countries

Southern Vietnam once declared that the country automatically inherited the rights of the former colonial power France, and also of territories occupied by Japan during the war. The latter decision was derived from the fact that during the San Francisco Conference of 1951, the Vietnamese representative had declared both the Paracel Islands and the Spratly Islands as part of Vietnam – and no objection had been brought forward. Yet during the Geneva Conference of 1954, France only conceded that Vietnam obtain the Paracel Islands, while France retain sovereignty over the Spratlys. South Vietnam continued to claim both archipelagoes on disputable historical/archaeological grounds. North Vietnam in 1958 weakened the arguments of the south by seemingly accepting the Chinese claims over the whole area, but at least the 12-nautcail miles zone around the islands.

After reunification Vietnam occupied several islands of both archipelagoes and so created faits accomplits much stronger than any of the older arguments. This happened in two steps, namely in 1975, and in 1988. Thereafter Vietnam also established a 200-miles exclusive economic zone (EEZ) around the islands, but now its claims are restricted to 12-mile zones around the islands, atolls and rocks, but nonetheless impede the Chinese of rights on these spots.

Philippine claims originated in 1950, in order to counter the occupation of Itu Aba (Taiping Dao 太平島) by the Republic of China (Taiwan). Six years later the private adventurer Tomas Cloma (1904-1996) asked the Philippine government to take over sovereignty over 50-odd islands in the region, but on pressure from the other powers in the regions, the state did not react. In 1971 President Ferdinand Marcos (President 1965-1986) revived this idea and claimed the Spratly islands in a protest note to Taiwan, with the argument that the former owner was Japan, but after the San Francisco Conference 1951 no new owner had been identified, and the islands since were res nullius (owned by nobody). A year later the archipelago was incorporated into Philippine territory with the name Kalayaan Islands, and an EEZ was established. The claim was formalized in 1978. Through the whole decade Philippine troops stood on several of the islets.

Encouraged by this claim, Malaysia argued with the location of the Spratly Islands on the continental shelf (1979) – while in the case of the Philippines, the archipelago was separated from the shelf by the Palawan trough. Malaysia also declared a 200-miles EEZ and occupied several islands.

Indonesia is not involved in the dispute, but became alarmed by a Chinese map with a boundary running through a gas field north of the Nantuna Islands, which are without doubt part of the territory of Indonesia.

The Sultanate of Brunei claims a continental shelf and its resources, but not the Louisa Reef included in the zone. Since 1988 its zone includes the Rifleman Bank and the Owen Shoal.

Taiwan's claims are identical to that of the PRC, and the country operates still a small base on Itu Aba.

Oil fields

During the 1960s several surveys of oil companies came to the result that there might be exploitable fields in the South China Sea. Brunei and Malaysia began drilling in the early 1970s. The oil price shock encouraged the Philippines to start oil and gas exploitation and in 1979 there were as many as nine offshore well in the Kalayaan archipelago (i.e. the Spratly Islands) whose yields covered about 15 per cent of the Philippine's oil consumption (Buszynski and Roberts 2015: 10). Chinese interest was stimulated by the activities of the Philippines, and a survey by the Economic Commission for Asia and the Far East (ECAFE) detected sizable reserves of oil in the region. Yet Chinese interest in the southern parts of the South China Sea was not only based on energy resources, but also on geostrategic ones.

After the end of the Vietnam War in 1975 it was clear that Vietnam sided with the Soviet Union, the arch-enemy of China. China desired to keep away Soviet naval presence from the region. Clashes intensified after the Sino-Vietnamese War in 1979. After several intensive geographical surveys, China decided in 1987 to show physical military presence and in February 1988 began with the construction of facilities on Fiery Cross (Yongshu Jiao 永暑礁) and several other reefs. In March, a serious confrontation with Vietnam led to the sinking of three Vietnamese vessels.

China thereafter tried to bolster her claims by legalizing them. In February 1992 the National People's Congress passed the "Law on the Territorial Sea and the Contiguous Zone" (Zhonghua renmin gongheguo linghai ji pilianqu fa 中华人民共和国领海及毗连区法). The law restated the "Declaration on the Territorial Sea" from 1958, but also stated that the "land territory" (ludi lingtu 陆地领土) of China included the mainland as well as several "affiliated islands". The term "territorial sea" (linghai 领海) referred to waters adjacent to „land territory" (12-mile zone). This meant that the Paracel and Spratly Islands were – like Taiwan – an integral part of Chinese territory. Yet in this law, China did not clearly define which islands and reefs exactly were considered being part of Chinese territory.

Quotation 1. Law on the Territorial Sea and the Contiguous Zone
第二条 Article 2
中华人民共和国领海为邻接中华人民共和国陆地领土和内水的一带海域。中华人民共和国的陆地领土包括中华人民共和国大陆及其沿海岛屿、台湾及其包括钓鱼岛在内的附属各岛、澎湖列岛、东沙群岛、西沙群岛、中沙群岛、南沙群岛以及其它一切属于中华人民共和国的岛屿。 The territorial sea of the People's Republic of China is the sea belt adjacent to the land territory and the internal waters of the People's Republic of China. The land territory of the People's Republic of China includes the mainland of the People's Republic of China and its coastal islands; Taiwan and all islands appertaining there to including the Diaoyu Islands; the Penghu Islands; the Dongsha Islands; the Xisha Islands; the Zhongsha Islands and the Nansha Islands; as well as all the other islands belonging to the People's Republic of China.

A few months later, the China National Offshore Oil Corporation (CNOOC, Zhongguo haiyang shiyou zong gongsi 中国海洋石油总公司) concluded an exploration contract with the American Crestone Energy Corporation. Vietnam countered this activity by signing a contract with Mobil in April 1992, and four years later with Conoco.

The other members of the ASEAN pact assumed that the whole affair was just an extension of the Sino-Vietnamese conflict and therefore took no side. Each of the members retained friendly bilateral relations with both sides, and the ASEAN itself did not react at all. In July 1992 the organization concluded, with China, the ASEAN Declaration on the South China Sea in which peaceful solutions over all disputes were recommended. China violated against the declaration in late 1994 by occupying the Mischief Reef (Meiji Jiao 美济礁) in the claim zone of the Philippines and building infrastructure on the spot. The Philippines protested, but the leadership of the ASEAN appealed to all sides to keep to the Declaration.

The Philippines thereupon strengthened their ties with the United States, concluding a Visiting Forces Agreement in 1998 (in force since May 1999). The ASEAN, on its side, sought again a peaceful solution and concluded a new Declaration of Conduct with the PRC in November 2002.

After 2009 China began asserting is claims for exclusive possession of the region, and to expel the other claimants. This step might have been encouraged by the weakness of the United States after the financial crisis, by a greater presence of military circles in Chinese foreign and security policy, and a growing nationalist tendency in domestic and foreign policy. China declared the region as a "core interest" and announced the determination to secure her maritime resources and strategic waters.

Chinese arguments went beyond the UNCLOS from 1982 and claimed that Chinese rights over the region as "historical waters of China" were based on old historical records – and were not bound to international law. Yet according to international law and precedent cases, traditional usage of the area for fishery is not sufficient for territorial claim. For such claims, a "continuous display of state authority" would be necessary (Buszynski and Roberts 2015: 5).

Table 1. Spots on the Spratly Islands occupied by China
Occupied by the People's Republic of China
Subi Reef 渚碧礁 Zhubi Jiao
Gaven Reef 南薰礁 Nanxun Jiao
Hughes Reef 东门礁 Dongmen Jiao
Johnson South Reef 赤瓜礁 Chigua Jiao
Fiery Cross Reef 永暑礁 Yongshu Jiao
Cuarteron Reef 华阳礁 Huayang Jiao
Mischief Reef 美济礁 Meiji Jiao
Occupied by the Republic of China (Taiwan)
Itu Aba Taiping Dao 太平島

China compensated for this defective "indisputable sovereignty" over the area with intensifying the harassment of the other claimants. The county built up a "fishery patrol" fleet under the State Oceanic Administration which carried out patrol missions and was ordered to protect maritime security in the waters by pushing aside or inspecting foreign vessels, mainly such from Vietnam and the Philippines. In 2013, the oceanic administration was reorganized for an integration of the coastguard, maritime surveillance and customs. Chinese surveillance ships also impede the free movement of oil exploration vessels of all ASEAN states, and China proclaimed a fishing ban around the Paracel Islands for certain months of the year which critically concerns Vietnamese fishers.

The national territorialization of the vague maritime frontier by the PRC also concerns countries not directly adjacent to the South China Sea. Exclusive territorial rights would endanger the free movement of naval traffic to the Middle East and Europe from Japan and South Korea, and the interests of Indian oil companies having invested in the South China Sea as well. The military use of bases on reefs in the area would also interfere into the security concepts of the United States, as bases in the South China Sea would expand the reach of the Chinese navy and its ordnance remarkably. Finally, the diverging interests of individual ASEAN members can be an issue tearing the association apart: Cambodia supports Chinese claims, while the Philippines (and Japan, Korea, and Taiwan as well) are a close ally of the United States.

Japan, experiencing similar acts of harassment by the Chinese navy in the case of the Diaoyu/Senkaku dispute, therefore supports Vietnam and the Philippines logistically and by associative means.

Solutions to the issue can first be seen in the preservation of the status quo, yet with the condition of avoiding mutual provocation to minimize the risk of escalation. Second, resolution over issues can only be achieved mutually, and not by imposition by a superior instance, in order to avoid sentiments of being treated unfair.

A first step in this direction was achieved by the "Declaration of the South China Sea", the "Code of Conduct" from 1992. The parties also conducted bilateral talks, for instance, China with the Philippines, or the latter with Vietnam. These negotiations led to the "Declaration on the Code of Conduct of the Parties" concluded in November 2002. Yet this declaration did not concretize the individual islands or the surrounding sea territory in question (Vietnam wanted to include the Paracel Islands, but China not), nor did it offer binding agreements on mechanisms of dispute resolution.

Even if China's ambitions in the area don't make it probable that China would sign a code of conduct, the country had several reasons to do so. First, to demonstrate moderation, second, to prevent the ASEAN members of venturing similar occupation and fortification of local spots, and third, to prevent the ASEAN to involve the United States.

A further step would be to conclude an agreement on incidents at sea, such as the one concluded in 1972 by the Soviet Union and the USA. China continues to explore oilfields in the region and to create infrastructure on the islands already occupied, like Fiery Cross, Subi (Zhubi Jiao 渚碧礁), and the Mischief reefs.

Sources/Further reading:
ASEAN (1992). "ASEAN Declaration on the South China Sea", ASEAN Economic Bulletin, 9/2: 240-241.

Bondoc, Jarius (2014). Faulty translations misled Beijing’s sea claims (
Friedman, George, Xander Snyder and Cheyenne Ligon (2016). Chinese Military Installations in the South China Sea (
Vuving, Alexander L. (2016). South China Sea: Who Occupies What in the Spratlys? (

AMTI Leadership (2015). Diplomacy Changes, Construction Continues: New Images of Mischief and Subi Reefs (, Asia Maritime Transparency Initiative).

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