The Vietnamese language belongs to the Mon-Khmer sub-family of the Austroasiatic language group. Most Vietnamese are Mahayana Buddhists, with some elements of Taoism and Confucianism. Their exact numbers in Cambodia today is a matter of some uncertainty, as many of them are possibly in the country illegally: they are thought to number between 100,000 (Taipei Times, July 2003) and more than 1 million (CIA World Factbook: Cambodia, 2007; based on the belief that the Vietnamese represent about 5 per cent of the total population of the country). Tensions between Vietnamese and Cambodia in recent years have apparently led to the departure of many.
While dispersed throughout the country, many Vietnamese are concentrated in the urban areas; others are involved in traditional fishing and agricultural activities.
Historically, Vietnamese emperors had a policy of settling Vietnamese in sparsely populated areas that the Khmer regarded as part of Cambodian territory. Vietnamese rice farmers and fishermen continued to migrate into Cambodia during the nineteenth and twentieth centuries. During the French colonial period, France staffed much of its colonial administration in Cambodia with French-speaking Catholic Vietnamese. The French also imported Vietnamese plantation workers. In the nineteenth century Vietnam permanently took over part of Cambodia, and, during one occupation of Phnom Penh, attempted to impose the Vietnamese language and political structures and Sinicized or Confucianized Vietnamese cultural norms and practices on the Hinduized Theravada Buddhist Khmers. Thus many Cambodian nationalists came to perceive Vietnamese as a threat not only to their political independence but also to the survival of the Khmer people and culture.
Under Prince Sihanouk's rule during the post-independence period, ethnic Vietnamese in Cambodia were, like ethnic Chinese, regarded as foreign residents. However, extreme Cambodian nationalists regarded ethnic Vietnamese as agents or instruments of a Vietnamese intention to take over Cambodia. Ethnic Vietnamese were severely persecuted under the successive regimes of Lon Nol (1970-5) and Pol Pot (1975-9). Almost immediately after Lon Nol's coup against Prince Sihanouk, pogroms were initiated against ethnic Vietnamese in Phnom Penh that left several thousand dead and caused more than 100,000 to flee back to Vietnam.
When the Khmer Rouge came to power in 1975 perhaps as many as 150,000 Vietnamese who had not fled or been expelled during the Lon Nol years were expelled to Vietnam. Those Vietnamese who remained, often because they were married to Khmer, were massacred, along with, in many instances, the children of mixed Khmer-Vietnamese families. While Cambodia was under Vietnamese occupation, ethnic Vietnamese who had been expelled during the Lon Nol and Pot Pot regimes returned to Cambodia. Additional Vietnamese artisans entered the country in response to an economic boom that followed the signing of the Cambodian peace treaty in 1991.
In the early 1990s the Khmer Rouge and some right-wing Cambodian politicians organized political assassinations of ethnic Vietnamese living in isolated fishing villages, which led to an exodus of perhaps 25,000 Vietnamese to the Cambodia-Vietnamese border. Vietnam admitted the majority of them.
Anti-Vietnamese sentiments remained so strong in the 1990s that a new immigration law - primarily aimed at the Vietnamese - which allows for the mass expulsion of non-citizens, was passed with a large majority in the elected Assembly, though the government pledged that there would be no mass expulsions.
The Vietnamese are the most vulnerable of Cambodia's minorities, and the most prone to discrimination and violations of their rights. Their status has much to do with the difficult history and relationship between Cambodia and Vietnam, which has helped create animosity and intolerance towards them. There are a few private schools teaching in Vietnamese; these are not officially sanctioned but neither have they encountered a great deal of resistance from state authorities. No state school provides any form of schooling in Vietnamese.
The current citizenship law of Cambodia makes it difficult for many of them to prove that they are citizens of Cambodia. This in turn severely limits their enjoyment of a variety of rights, and excludes them from fully participating as equal members in the political and economic life of the country. The discriminatory impact of this legislation, the loss or destruction of identity papers which occurred during the upheavals from the 1970s, and the fact that the Constitution of Cambodia only assigns the protection of human rights to citizens, leaves them particularly vulnerable.
Some Vietnamese are probably illegal immigrants, in the sense that they settled in Cambodia after the Vietnamese army overthrew the Khmer Rouge. However, it is likely that many of them were in fact Cambodian citizens who had fled the country during the period of Khmer Rouge rule. Because they are not ethnically ‘Khmer', the presumption of authorities continues to be that they are probably illegal immigrants. Unless they have identity papers demonstrating their Cambodian nationality, they risk losing their land or homes that they may have occupied for decades.
There continued to be some reports in 2006 of state officials evicting ethnic Vietnamese from their floating villages around Tonle Sap Lake, and even of seizing and destroying identity papers which might establish some of them as being Cambodian citizens.
Though not due to any official Cambodian government policy, any expression of distinct Vietnamese identity is still occasionally met with violence; people are occasionally set upon if they are heard to speak in Vietnamese. Even politicians considered ‘democratic' by outsiders periodically revert to slogans against the Vietnamese minority, describing them as a ‘yuon' threat, a word which can have a derogatory meaning. There have been reports of some Vietnamese who have been recognized as citizens being prevented from voting in 2003 and in later local elections.