Brief History of Vietnamese Expansionism vis-à-vis Cambodia

Brief History of Vietnamese Expansionism vis-à-vis Cambodia

In 1941, Ho created the Viet Minh, an abbreviation of “Vietnam Doc Lap Dong Minh Hoi,” or “League for the Independence of Vietnam,” and spread its anti-French activities to Laos and Cambodia, where the Viet Minh later fragmentized the anti-French local Khmer Issarak front into a Khmer Viet Minh front. In 1949, the Viet Minh instituted the “Ban Van Dong Thanh Lap Dang Nhan Cach Mang Cao Mien” (“Canvassing Committee for the Creation of the Revolutionary Kampuchean People’s Party”) and created the Kampuchean People’s Liberation Army in 1950.

By Gaffar Peang-Meth
Professor of Political Science (retired)
University of Guam
Originally posted at:

On Christmas Eve 1978, more than 100,000 Vietnamese troops, backed by tanks and aircraft, crossed the border into Cambodia. In 14 days of fighting, Hanoi’s army sent Pol Pot and his Khmer Rouge fleeing. The Vietnamese captured Phnom Penh Jan. 7, 1979, installed a puppet regime and stayed for the next 10 years.

For victims of Pol Pot’s genocidal rule, which began April 17, 1975 and resulted in the deaths of upwards of two million people, Jan.7, 1979 was the day of deliverance by Vietnam. Surely, Vietnam was their “savior” and their “liberator” at a time when the world watched and did nothing about the horrors of the Killing Fields. However, for many Cambodians, Jan. 7th is also a day of infamy. Pol Pot was replaced by those referred to as Cambodians with Khmer bodies but Vietnamese heads, the Khmer Viet Minh. This cohort was created by the Vietnamese Communist Lao Dong, trained at the Son Tay Military Academy and the Nguyen Ai Quoc political school, and led by a disgruntled regional field commander, Hun Sen, who became indebted to Hanoi for his return to power. Many Cambodians felt that substituting the Khmer Viet Minh for the Khmer Rouge was like replacing cholera with the plague.

A host of foreign governments also worried. The world was still governed by the well-specified rule of law founded on the principle of absolute, comprehensive, permanent and inviolable sovereignty and independence. As Singapore argued before the international community at the United Nations, the world is no longer safe, and peace and security are no longer assured, if a more powerful state is allowed to invade a weaker one like Vietnam had done. The Association of South East Asian Nations spearheaded calls for Vietnam to withdraw its troops from Cambodia.

As a result, the United Nations and other international organizations became a political-diplomatic battleground for many years between proponents and opponents of Vietnam’s invasion. And so it was that the anti-Vietnamese Khmer Resistance was born, first as separate armed bands with similar goals, and later as a loose coalition of Cambodians of the fallen Khmer Republic, Cambodians of the monarchy, and the leftovers of the Khmer Rouge. Despite their differences, they worked together toward pressuring Vietnam into withdrawal and to seek Cambodian self-determination.

Cambodian nationalists assert that Vietnam attacked Pol Pot in 1979 because he became too independent of Hanoi. The invasion was initiated to bring the insolent back into line. Since 1979, they have asked: If Vietnam’s goal was to “save” and “liberate” the Cambodian people from Pol Pot, what prevented Vietnam from surrendering a freed Cambodia and her people to work with the world community to build a new government and social order? Would not Vietnam have received profound gratitude by ceding to the United Nations the role of assisting Cambodians’ self-determination rather than imposing 10 years of foreign occupation?


Hanoi, like the rest of the world, knew that Pol Pot’s agents had perpetrated brutalities against the Khmer people since April 17, 1975, when the Khmer Rouge forced the evacuation of the entire Cambodian population from homes, villages, towns and cities and took them to perform forced labor. Suffering, death and destruction were the order of the day.

The widely reported burning of homes and massacres of civilians in Vietnam’s An Giang and Chau Doc provinces in 1977 by Pol Pot’s guerrilla units offered an incitement to Vietnam, which was then busy strategizing and plotting Ho Chi Minh’s grand design of a greater Vietnam. The Khmer Rouge’s belligerence gave the Vietnamese even more reason to put in play a takeover plan that would advance its goal of a federation of Vietnam, Cambodia and Laos.

It is no coincidence that Vietnamese troops invaded Cambodia on the same day Brezhnev’s Soviet 40th Army entered Afghanistan, Dec. 24, 1979. The Soviet Union was Vietnam’s chief ally and financial supporter at the time. Following the regime change in Moscow in May 1988, the Soviets began to exit Afghanistan one month after Gorbachev announced they would. Meanwhile, Hanoi was working on an exit strategy of its own.

Vietnam observed the rapid changes under way around the world: in the Soviet Union and Eastern Europe, communism was in retreat; rival China was on the rise; and U.S.-China relations was warming and mutually supportive of the anti-Vietnamese Khmer Resistance. While Vietnam began to hint at its eventual withdrawal from Cambodia, it took offensive military action against the Cambodian resistance. Hanoi maneuvered to weaken the anti-Vietnam U.S.-China alliance by encouraging talks between the Vietnam-created regime in Cambodia and the resistance factions. The talks were also designed to improve the puppet government’s legitimacy. By the time withdrawal of Vietnamese forces from Cambodia began in December 1989 (11 years after the initial invasion), Vietnam had ensured that its Cambodian subordinates, the Khmer Viet Minh, were entrenched in Cambodia’s administrative and governmental organizations.


As French critic Jean-Baptiste Alphonse Karr said, “Plus ça change, plus c’est la même chose,” or, “The more things change, the more they remain the same.” Look at the history of relations between Cambodia and Vietnam for affirmation.

The Vietnamese southward expansion after Nam Viet freed itself in 939 from a thousand-year Chinese bondage was described by Vietnamese scholar Nguyen The Anh in “Le Nam Tien dans les textes Vietnamiens,” as a centuries-long phenomenon called “Nam Tien” (progression southwards), “one of Vietnam’s history’s constants.” Anh described the “sparsely populated and accessible land available for [Vietnamese] rice growers” to the south as “favorable for encroachment.” Vietnamese “Confucian persuasion” was abandoned in favor of “an action resolutely imperialistic” to grab land and impose Vietnamese “administrative and cultural practice … to better integrate [the new area] into the Vietnamese space.” The migration was ongoing, even as other kingdoms were encountered. In 1406, the ancient kingdom of Champa’s capital, Vijaya, was seized and the kingdom was extinguished in 1471. Then, in 1630, Vietnamese princess Ngoc Van, married to Khmer King Chey Chetha II, promoted Vietnamese settlements in the low delta Khmer territory of Preah Suakea (Ba Ria) and Prey Nokor (Saigon).

Historical records reveal that until the French protectorate was established in 1863, Cambodia was a battlefield for Thai and Vietnamese armies that fought on Khmer soil. Khmer dynastic quarrels led separate royal factions to seek support from Bangkok and Hue. Cambodia was known as a “two-headed bird” – a tributary state to both foreign capitals. In 1833, after Vietnam defeated the Thais in Cambodia, the bird head pointed toward Hue, and Vietnamization of Cambodia began in earnest: Vietnam installed teenager Ang Mey as queen, Cambodia’s capital was renamed “Nam Viang,” Cambodia’s reorganization followed Vietnamese administrative lines, and authorities adopted Vietnamese names, customs and dress. In 1840, the Cambodian government was seated in Saigon, and Cambodia’s name was changed to “Tran Tay” (western commandery).


Opponents of Vietnam’s 1978 invasion see Hun Sen and his ruling Cambodian People’s Party as a force seeking integration of Cambodia into the late Ho Chin Minh’s dream of a federation of former French Indochinese states of Vietnam, Cambodia and Laos. As has been the case many times in history, Cambodians have connived with the Vietnamese to accomplish Vietnam’s goals: Khmer King Chey Chettha II in 1620, King Ang Chan II in the 1800s, Prince Sihanouk in the Vietnam War, Pol Pot and Paris-trained Khmer Marxists, Hun Sen and his ruling Cambodian People’s Party, supported by the King Father Sihanouk and his son Sihamoni, the current king.

What started as Nam Viet’s search for security and growth became a strategy for expansionism. The intention to expand its influence is illustrated even in the name of the political party founded in 1930 by Ho Chi Minh – the “Communist Party of Indochina.” Ho did not just want to liberate Vietnam from the French; he defined the task of the CPI “to make Indochina completely independent.”

In 1941, Ho created the Viet Minh, an abbreviation of “Vietnam Doc Lap Dong Minh Hoi,” or “League for the Independence of Vietnam,” and spread its anti-French activities to Laos and Cambodia, where the Viet Minh later fragmentized the anti-French local Khmer Issarak front into a Khmer Viet Minh front. In 1949, the Viet Minh instituted the “Ban Van Dong Thanh Lap Dang Nhan Cach Mang Cao Mien” (“Canvassing Committee for the Creation of the Revolutionary Kampuchean People’s Party”) and created the Kampuchean People’s Liberation Army in 1950.

Although the CPI was dissolved to publicly demonstrate Vietnam did not harbor expansionist intentions toward its neighbors, it resurfaced in February 1951 as the Lao Dong (Vietnam Workers’ Party) with the same agenda. The Lao Dong’s goal of integrating Cambodia into a Greater Vietnam may be read in its political report which stated: “We must strive to help our Cambodian and Laotian brothers … and arrive at setting up a Vietnam-Cambodian-Laotian Front” against the French. A month later the “Joint National United Front for Indochina” was formed. In November of that year, the Revolutionary Kampuchean People’s Party was created with name and statute drafted in the Vietnamese language. It has been said the RKPP and the Cambodian local Communist Pracheachon Party were one and the same. As Prince Sihanouk wrote in February 1960, the Pracheachon Party was “working indefatigably … and specifically to bring Cambodia under the heel of North Vietnam.”

Brian Crozier, a former Reuters correspondent, quoted a captured November 1951 Viet Minh document exhibiting Vietnam’s hegemonic attitude: “The Vietnamese Party reserves the right to supervise the activities of its brother parties in Cambodia and Laos.” Crozier also quoted a Viet Minh radio broadcast of April 1953: “The Lao Dong Party and the people of Vietnam have the mission to make revolution in Cambodia and Laos. We, the Viet Minh elements, have been sent to serve this revolution and to build the union of Vietnam, Cambodia, and Laos.” Viet Minh administrations with their own armed forces and system of tax collection were established in Cambodia and Laos. A Hanoi-created “Kampuchean Resistance Government” emerged in 1952 to rival Sihanouk’s Royal Government.

When the July 1954 Geneva Accords ordered Viet Minh forces to leave Cambodia, they took with them between 4,500 (a conservative figure) and 8,000 Cambodians (reportedly claimed by Vo Nguyen Giap in 1971), mostly young children, to be raised, cultured and given political and military training in Vietnam. These Cambodians with “Khmer bodies but Vietnamese heads” returned to Cambodia after 1970 to fight Lon Nol, and to unsuccessfully wrest control of the Communist Party of Kampuchea from Pol Pot. Some were arrested, others purged.

According to Khmer Rouge leader Pol Pot, the Marxist-Leninist Communist Party of Kampuchea was born on Sept. 30, 1960, after the first party congress of 21 people met for three days and three nights. Pol Pot asserted that a Cambodian revolutionary movement that “truly belonged to our people” existed prior to the Geneva Convention, but its dissolution after the 1954 agreement was acknowledged because “people lacked a correct and enlightened guideline.” Pol Pot described 1968 as the year when armed struggle – civil war – began.

Undoubtedly, Hanoi was aware that its publicly proclaimed “fraternal brothers and sisters,” the Khmer Rouge, were not so “fraternal” privately, and it knew its relationship with the Khmer Rouge was unsatisfactory. But Hanoi let the Khmer Rouge be while it looked to building its own Kampuchean puppets. Hanoi was biding its time. And as it was fighting a war against the Americans in Vietnam, Hanoi threw in its battle-tested troops to fight Lon Nol’s republican army, enemies of Prince Sihanouk who had allied himself with Hanoi. It was Hanoi’s troops that routed Lon Nol’s army and put Pol Pot in power in Phnom Penh.

Neither Hanoi nor the world governments intervened to stop the genocide that followed. However, when the Khmer Rouge’s fierce independence of Hanoi was more than the latter would tolerate, Hanoi concluded it was time to teach its insolent comrades a lesson. On Nov. 3, 1978, Hanoi signed a 25-year peace and cooperation treaty with Moscow. A month later, on Dec. 3, Hanoi Radio announced the birth of the “Kampuchean National United Front of National Salvation,” led by a 14-member Central Committee under Heng Samrin, a former commander of the Khmer Rouge’s 4th Division. Hun Sen was a former chief of staff and regimental deputy commander in Sector 21. By the end of the month, Vietnamese troops would lead 18,000 KNUFNS soldiers across the border into Cambodia. Phnom Penh was soon captured and a subservient regime installed. On Feb. 18, 1979, master and puppet comrades signed a 25-year treaty of peace, friendship and cooperation, a treaty that effectively integrated Cambodia into a Greater Vietnam.


The 1979 friendship-cooperation treaty brings Hanoi’s influence as far west as the border with Thailand. The treaty binds Cambodia and Vietnam in what it terms “militant solidarity and fraternal friendship.” As people educated in the culture of Confucianism, Vietnamese leaders’ actions are generally carefully thought-out and calculated to maximize Vietnam’s interests. They know what they want, what their national interests are, and they move methodically to attain them. Unfortunately for Khmers and their country, King Sihamoni, son of King Father Sihanouk, signed the supplements to the treaty, giving Vietnamese full access to colonize and Vietnamize Cambodia. In the stroke of a pen, the signatories extol a symbiosis of interests between Cambodia and Vietnam. Retired Johns Hopkins professor Naranhkiri Tith observes on his Web site that the 1979 treaty between Hanoi and its puppet in Phnom Penh “became official in 2005” when Cambodia’s King Sihamoni, “with the support of his father Sihanouk,” put his royal signature on “supplements” to the treaty, thereby making Cambodians complicit in the Vietnamization of Cambodia.

In its preamble, the treaty cites the “closely interrelated” independence, freedom, peace and security of Vietnam and Cambodia – what affects one affects the other – and that both countries are “duty-bound to help each other wholeheartedly and with all their might” safeguard and consolidate the products of their “revolution.” It cites both countries’ “militant solidarity” and “long-term and all-round cooperation and friendship” as representing their “vital interests.”

In the treaty’s first three articles, the Cambodians hand Ho Chi Minh the goal of an Indochinese alliance he had dreamed about.

In Article 1, the two countries pledge to “do all they can” to maintain their “traditions of militant solidarity” and to develop “mutual trust and assistance in all fields.”
In Article 2, they pledge to “wholeheartedly support and assist each other in all domains and in all necessary forms,” as well as to take “effective measures to implement this commitment whenever one of them requires.” Cambodian leader Hun Sen can “require” Vietnamese intervention and he will be assisted “in all domains and in all necessary forms,” and vice versa.
In Article 3, both countries pledge “mutual fraternal exchanges and cooperation” and mutual assistance in the economic, cultural, educational, public health, scientific, and technological fields, as well as the training of cadres and the exchange of “specialists and experience in all fields of national construction.” This opens the door for Vietnam to operate in Cambodia. For example, Vietnam has always been short of food, and Cambodia is historically rich in fertile land and fish and natural resources.
Subsequent sections of the treaty further reinforce this dictate of Cambodian-Vietnamese interdependence.
Article 4 stipulates a border agreement based on the “present border line.”
Article 5 pledges a “long-standing tradition of militant solidarity and fraternal friendship” to which both parties “attach great importance.”
Article 6 requires that the parties “frequently exchange views” on all questions concerning both countries’ relationships and on “international matters of mutual interest.”
Articles 7, 8, 9, speak of the right and obligation of each party to any bilateral and multilateral agreements.

In 1962, Prince Sihanouk wrote: “Whether he is called Gia Long, Ho Chi Minh, or Ngo Dinh Diem, no [Vietnamese] will sleep soundly until he succeeds in pushing the Khmer toward annihilation, after having made them go through the stage of slavery.” Pol Pot and his French-trained Marxists handed Cambodia to Vietnam. Then Heng Samrin and company agreed to a Vietnamized Cambodia. Important stipulations in the Paris Peace Accords on Cambodia signed in October 1991 were not implemented, allowing Vietnam’s surrogate, Hun Sen, to elbow his way into becoming a co-prime minister despite losing the 1993 general elections. The co-premiership formula was devised by Sihanouk to benefit Hen Sen at the expense of Sihanouk’s own son, Ranariddh. It gave Ranariddh, winner of the election, the title of 1st Prime Minister, and the loser of the election, Hun Sen, the title of 2nd Prime Minister. Dissatisfied with his subservient position in the dual premiership, Hun Sen unleashed a coup d’etat in 1997 in which hundreds were killed and seized power.


The journey toward a greater Vietnam has not ended. What began in 939 when Nam Viet freed itself from Chinese bondage has in 2010 put the Vietnamese at Thailand’s border and in a position to have an impact on Thailand’s political stability. Cambodians are being manipulated by Hun Sen to respond to Thailand based on historical animosities not relevant to today’s political realities. It would be preferable if lessons could be taken from history so that it is not repeated.

The current Cambodian-Thai conflict has been inflamed by Hun Sen’s continuing provocations, intended to destabilize Thailand and provide opportunities for Vietnam to influence events there. Hun Sen’s success at diverting his countrymen’s attention from their own meager lots to the possibility of a conflict with their historical adversary has had the side benefit of increasing domestic support for his regime. The recently revealed “classified” contingency plan by Thailand for military action against Cambodia, should the Thai-Khmer dispute escalate, is seen by Professor Naranhkiri Tith as “exactly what Hun Sen wanted.” Logically, the Treaty of Peace, Friendship and Cooperation between Hun Sen’s Cambodia and Vietnam is an important instrument for him to invite Hanoi’s troops – the “liberators” against Pol Pot – to help fight the Thais on Khmer soil, another repeat of history.

Hun Sen has successfully used governmental administrative machinery to keep Cambodians intimidated and ignorant of their civil rights and the principles of good governance. He dangles showy projects and physical improvements to infrastructure, while many scavenge the city’s dumps and live on rodent meat. Of late, he has taken to publicly cursing the Thai leadership seemingly daily. His call to protect Cambodia’s Preah Vihear Temple from the Thais brings many Cambodians to his side, though they are mute over Vietnamese encroachment from the east. Those who dare speak out against Vietnamese expansionism are silenced through intimidation or imprisonment.
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About the author:

Gaffar Peang-Meth of Russey-keo, Phnom Penh, holds a Ph.D. in political science (comparative governments and politics, Southeast Asia) from the University of Michigan in 1980, served in the Khmer People’s National Liberation Front at Banteay Ampil in 1980-1989, and taught at Johns Hopkins in 1990 and at the University of Guam in 1991-2004. He is retired, and now lives in the United States. He can be contacted at