Purpose .

Vietnam used to invade Cambodia is commonly known among modern Vietnamese people in the South. In our team, even those from the North and Central of Vietnam have rarely heard about the genocide of Pol Pot regime. In this project, we wish to reevaluate the intervention of Vietnam into the genocide of the Red Khmer Rouge regime back in Vietnam-Cambodia War 1979 in order to understand the postulated causes leading to two opposite viewpoints of both the Vietnamese and Cambodian government and citizens.

Historical background .

Indochinese Communist Party Establishment

During World War II, Cambodia and Vietnam were against the French colonization and burst out of the national revolution. The communist movement in Cambodia was strongly developed

Geneva Conference

Vietnamese communists withdrew from Cambodia

Cambodian Coup

March 1970
Sihanouk was expelled by the pro-American ally - Lon Nol. Lon Nol's government attacked Khmer Rouge and the National Liberation Front at Cambodia's southeast border

The Conquer for ancient land

The Khmer Rouge attacked the territory in the southeast Vietnam to take back the ancient land. However, Vietnam did not have immediate actions toward invasion

Cold War

The conflict between capitalism (led by the U.S) and communism (led by the Soviet Union) "affected on international isolation and economic hardship"

Vietnam War

North Vietnam forces and the National Liberation Front were fighting against the American and the Republic of Vietnam. Because of this event, DRV could not fully control the political situation of Cambodia

The Khmer Republic Establishment

October 1970
Lon Nol established the pro-American government to fight against the Communist

Clashes broke out between Cambodia and Vietnam

December 1977
The end of political and diplomatic relations between Khmer Rouge and Democratic Republic of Vietnam

Khmer People’s Revolutionary Party Establishment

KPRP was established by the guided of Vietnam Communist Party. Prince Norodom Sihanouk was supported to be the representative of the Party

KPRP under the lead of Pol Pot

Pol Pot became the new leader and general secretary of KPRP, overthown the existing the regime which did not follow the direction of Democrative Republic of Vietnam. KPRP was changed into Communist Party of Kampuchea

Khmer Rouge counter-attack

The Khmer Rouge took back the major territory and authoriity. In 1975, Lon Nol's goverment was completely defeated

Cambodian–Vietnamese War

Khmer Rouge attacked Ba Chuc. Vietnamese troops fought their way into Cambodia.

The Engagement of Pol Pot

Pol Pot and his Cambodian radical intellectuals studying abroad in Paris engaged in the Party and were influenced by the Chauvinism and Maoism

Operation Menu of the U.S

The U.S and the Republic of Vietnam boomed Khmer Rouge and Democratic Republic of Vietnam's territories

Democratic Kampuchea

Pol Pot reformed the country with new policies including the collectivization of all private property, the genocide and the allies with China and the U.S

Vietnamese troops captured Phnom Penh

Pol Pot Regime became the exilled government in Thailand's border. The new government called the People of Kampuchea Party was established under the intervention of Vietnam

Complex "brotherhood" .



Vietnam’s thoughts in keeping the relation with Cambodia
Social Darwinism
INDOCHINE FRANCAIS - Poster designed by Lucien Boucher (French, 1889–1971) for AIR FRANCE in the 40s   Poster qu?ng cáo c?a Hãng hàng không AIR FRANCE  Artist: Lucien Boucher (French, 1889–1971)  Size: 99 x 65 cm. (39 x 25.6 in.)  -----------------------  COLLECTION NAME: David Rumsey Historical Map Collection Record  Author: Boucher, Lucien (1889-1971) Date: 1945 Short Title: Indochine Francaise Publisher: Perceval Publisher Location: Paris Publisher: L’Association Nationale de L’Indochine Francaise Publisher Location: Paris Type: Separate Map Obj Height cm: 90 Obj Width cm: 59 Note: Date estimated. Country: Vietnam Country: Laos Country: Cambodia Region: Indochina Subject: Pictorial map Full Title: Indochine Francaise List No: 10232.000 Publication Author: Boucher, Lucien (1889-1971) Pub Date: 1945 Pub Title: Indochine Francaise Pub Note: "This striking & highly decorative poster map of French Indochina was designed by the renowned French affichiste and illustrator, Lucien Boucher [1889-1971]. Printed by the firm of Perceval, Paris, it was originally commissioned by the Association Nationale de L'Indochine Francaise. The original publication date of the poster is hard to determine precisely. Many authorities have dated it to circa 1938-40, but available evidence suggests this is highly unlikely. The Association Nationale de L'Indochine Francaise appears to have been founded under the auspices of the Free French administration in Algiers in August 1943. Its stated objectives were to try and maintain an enduring & unbreakable bond between France and her South East Asian territories throughout the duration of war and during its inevitably problematic aftermath. Most of France's South East Asia colonial administrations had remained nominally loyal to the pro-Nazi Vichy regime during the early years of the war, enduring an often uneasy relationship with local Japanese occupation forces who had moved into French Indochina in December 1941. With D-Day in June 1944 and t
Ho Chi Minh Trail

Social Culture

Military Strategy

Political Movement

Vietnamese society had long been embedded with the ideology of Social-Darwinism. Cambodia was a neighboring country that had the same yellow race and the same culture as Vietnam.
Cambodia’s situation was quite similar to what Vietnam overcame, which was colonized by the French and needed liberation
Vietnam recognized the necessity for Cambodia's border defense: solidifying the border security of the nation and serving as war supports.
  • Social Culture
  • Military Strategy
  • Political Movement
Vietnam was in the duty of an “older brother” who should help the “younger brother” to “strengthen the revolutionary base in Cambodia and guide this country along the path of socialism.”

A look into .

1979 Assembly
ECCC Case 002

1979 Assembly


Ieng Sary requested an emergency meeting from the UN Security Council to condemn Vietnam
Prince Sihanouk requestede aid of the U.S and the U.N . He said: “I hope the United States and the great American people will help us to expel the Vietnamese from Cambodia"
5 ASEAN Countries - Thailand, the Philippines, Malaysia, Indonesia, and Singapore - requested the intervention of Vietnam into Cambodia and apprehended the regional security
Nov 14th 1979
The 1979 United Nations Security Council election was held from 26 October 1979 to 7 January 1980 during the Thirty-fourth session of the United Nations General Assembly, held at United Nations Headquarters in New York City, including the Kampuchea Situation



Norodorm Sihanouk

Representative of Communist Party of Kampuchea at the U.N Securiity Council 1979
i (1)

Pol Pot

General Secretary of the Communist Party of Kampuchea
Nuon_Chea (1)

Nuon Chea

Prime Minister of Democratic Kampuchea.

Ieng Sary

Deputy Prime Minister of Democratic Kampuchea.
Chairman_Khieu_Samphan (1)

Khieu Samphan

Chairman of the State Presidium of Democratic Kampuchea
c68b8280d2a411e6a6591d07bc912d86 (1)

Le Duan

General Secretary of the Central Committee of the Communist Party of Vietnam
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Ton Duc Thang

The first president of the reunified Vietnam

Truong Chinh

General Secretary of the Central Committee of the Communist Party of Vietnam
32612044848_26b2ff99b9_b (1)

Ha Van Lau

Representative of Vietnam at the U.N Security Council 1979

Hun Sen

Deputy Prime Minister of People's Republic of Kampuchea/State of Cambodia
download (1)

Jimmy Carter

The 39th president of the United States
deng-xiaoping-9271644-1-402 (1)

Deng Xiaoping

The paramount leader of the People's Republic of China


The vote of 140 countries about the ousted Pol Pot Regime
Keeping the official chair in the U.N 50.7%
Vancant chair of Cambodia 25%
Abstention 24.3%
The call for the immediate withdrawal of all foreign troops of 15 security council members
Accept 86.7%
Veto 14.3%

Response in the U.N Security Council 1979

Hitlerian Vietnamese aggressors

Khmer Regime Response

Sihanouk expressed his admiration for the United States’s reactions towards Vietnam’s invasion, which was “justice,” and sought their support to abolish Vietnam out of Cambodian territory

Hitlerian Vietnamese aggressors

Foreign force

The U.N. Response

Strongly appeals to all States and national and international humanitarian organizations to render, on an urgent and non-discriminatory basis, humanitarian relief to the civilian population of Kampuchea, including those who have sought refuge in neighboring countries

Foreign force


Vietnam Response

The Vietnamese army just only defended the territory in the border area between these two countries during the Vietnamese-Cambodian War. Vietnam did not intervene into the ‘brother’ region. The internal uprising of Kampuchean was not relevant to Vietnam.



The diplomat avocation of Vietnam in the U.N Security Council

"In two weeks, the world will have forgotten the Kampuchea problem" - Ha Van Lau -

The different reactions

The U.N Security Council did not ignore this problem in "two weeks" but alarmed it, which led to the continous ten-year meetings. It was attracted by the media and the International community. In the research, some analysts argued that Vietnam forgot including the humanitarian reasons for their intervention, which prevented Vietnam from persuading the right of their intervention.
  • Vietnam actions
  • Historian suggestions

Vietnam’s omission of humanitarian reasons

The suggestion of historians

They think that humanitarian reasons should be used because:
‘Why does the UN recognise Pol Pot? The UN should help us capture Pol Pot – why are they protecting him?’ Many correspondents found themselves facing the same despairing questions: ‘How can it be?’ ‘Don’t they know Pol Pot killed my husband and my two brothers?’ ‘They killed my whole family and yet why does the UN support them?’
Irish Time - Tom Fawthrop - the interview of insiders

Common Reactions .

Governments' Reactions in 2019

Document Recommendation .

  1. Goscha, Christopher. 2006. Vietnam, the Third Indochina War and the meltdown of Asian internationalism . UQAM – Université du Québec à Montréal.
  2. Kiernan, Ben. 1999. Cambodia’s Twisted Path to Justice . Yale University Press—. 1996. The Pol Pot Regime: Race, Power, and Genocide in Cambodia Under the Khmer Rouge, 1975-79 . Yale University Press.
  3. Morris, Stephen J. 1999. Why Vietnam Invaded Cambodia: Political Culture and the Causes of War . Stanford University Press.
  4. Mosyakov, Dmitry. 2004. “The Khmer Rouge and the Vietnamese Communists: A History of Their Relations as Told in the Soviet Archives.” GSP Working Paper (Yale Center for International and Area Studies).
  5. Path, Kosal. 2018. Việt Nam và Campuchia 1975-78: Đánh giá sai về nhau? December 12. Accessed November 25, 2019. https://www.bbc.com/vietnamese/forum-46554653.
  6. Wheeler, Nicholas J. 2002. Saving Strangers: Humanitarian Intervention in International Society. Oxford Scholarship Online
  7. Noun Chea’s closing brief in case 002/02
  8. “Treatment of the Vietnamese | Drupal.” Accessed December 16, 2019. https://www.eccc.gov.kh/en/node/33820?fbclid=IwAR2Y1ui9utD_Gg7NeXe9nDYYw6rk1IS7OQKrWVVRQCjjyclPGvpqMZwJvIM.
  9. Andrew Nachemson. “Expert Says Vietnam Tried, Failed to Control Khmer Rouge | Phnom Penh Post.” Accessed December 16, 2019. https://www.phnompenhpost.com/national/expert-says-vietnam-tried-failed-control-khmer-rouge.
  10. Julia Brower, Ryan Liss, Tina Thomas, & Jacob Victor, Historical Examples of Unauthorized Humanitarian Intervention, (2003)
  11. Mahbubani Kishore, The Kampuchean Problem: A Southeast Asian Perception (January, 2009) , https://www.foreignaffairs.com/articles/asia/1983-12-01/kampuchean-problem-southeast-asian-perception.
  12. United Nations, Letter dated 12 October 1979 from the Permanent Representative of Viet Nam to the United Nations addressed to the Secretary-General, (1979)
  13. Kishore Mahbubani, The Kampuchean Problem: A Southeast Asian Perception, (Winter 1983/84), https://www.foreignaffairs.com/articles/asia/1983-12-01/kampuchean-problem-southeast-asian-perception
  14. Nicholas J.Wheeler, Saving Strangers: Humanitarian Intervention in International Society
  15. Gary Klintworth, Vietnam’s Intervention in Cambodia in International Law
  16. Doyle, Kevin. “Vietnam’s Forgotten Cambodian War”. BBC News, 14 Tháng Chín 2014, sec Asia. https://www.bbc.com/news/world-asia-29106034.
  17. Franck, Thomas M. Recourse to force: state action against threats and armed attacks. Hersch Lauterpacht memorial lectures. Cambridge ; New York, NY: Cambridge University Press, 2002.
  18. Sullivan , Meg . “UCLA Demographer Produces Best Estimate yet of Cambodia’s Death Toll under Pol Pot”. UCLA, 16 Tháng Tư 2015. http://newsroom.ucla.edu/releases/ucla-demographer-produces-best-estimate-yet-of-cambodias-death-toll-under-pol-pot.

Our Team .

Nguyễn Minh Hà

Nguyễn Thị Thanh Lam

Dư Quỳnh Thục Nhiên

Lê Đăng Quang

Nguyễn Lê Thuỳ Đan

Nguyễn Ngọc Trâm

Vũ Đức Huy

Special thanks to: .

Prof. Nguyen Nam

Vietnamese Studies Instructor
Fulbright University Vietnam

Prof. Andrew H. Bellisari

Vietnamese Studies Instructor
Fulbright University Vietnam

Ms. Tram Luong

Vietnamese Studies Teaching Assistant
Fulbright University Vietnam

Mr. Hoang M Vu

Ph.D in History
Cornell University