Condensed notes for A Level OCR Cold War exam on Cambodia


  • After gaining independence from France in 1954, Cambodia was governed by King Sihanouk until 1970. He tried to maintain Cambodian Cold War neutrality, but his country suffered Vietnamese and American attacks/invasions as the war in neighbouring Vietnam spilled over into Cambodia.
  • After General Lon Nol led a coup against Sihanouk, Nixon greatly escalated US involvement and carpet-bombed Cambodia. US intervention and aid ceased after the Vietnam War ended in 1963, which left the incompetent Lon Nol regime vulnerable and led to the establishment of Pol Pot’s Communist government in 1975.
  • The murderous regime of Pol Pot and the Khmer Rouge was overthrown by the Vietnamese in 1978, which elicited international condemnation and prompted a punitive invasion of Vietnam by Pol Pot’s Chinese allies.
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  • After a decade of Vietnamese occupation, the United Nations organised a new coalition government in 1933.
  •  The tearing apart of Cambodia by internal factions and external intervention can be split into the following sections:
  1. Sihanouk (1955-70).
  2. US bombing and the fall of the of the Khmer Republic (1970-5). 
  3. Pol Pot and Democratic Kampuchea (1975-8).
  4. The Vietnamese invasion (1978) and its consequences.
  • Cambodia was a predominantly Buddhist nation. 80% of the Cambodian people were peasants and ethnic Khmers. The capital of Phnom Penh was made up of a mixture of ethnicities form China and Vietnam and was only 20% Khmer.
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  • 1920-30’s Anti-colonialist movement emerged.
  • 1941 Sihanouk crowned.
  • 1954 July Cambodian independence from France...              Sept SEATO established.
  • 1955 Sihanouk advocated neutrality at Bandung.
  • 1967 Cambodian Communist Party’s armed insurgency began.
  • 1969 March US secretly bombed Cambodia.
  • 1970 March 18th Lon Nol overthrew Sihanouk.

  March-April ARVN and US attacked Communist bases in Cambodia. June US ground forces withdrew from Cambodia. 1971 Jan :US Congress prohibited use of American troops in Laos or Cambodia.

  • 1973 Aug US stopped bombing Cambodia.
  • 1975 April Pol Pot’s Democratic Kampuchea established.
  • 1978: Vietnamese invaded Cambodia.
  • 1979-85 Vietnamese installed Hen Samrin headed People’s Republic of Kampuchea.
  • 1985: Vietnamese-backed Hun Sen headed PRK.
  • 1991-3 UN involvement in Cambodia.
  • 1993 Elections resulted in co-premiership of Hun Sen and Prince Ranarriddh.
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SIHANOUK (1955-70)

Khmer: Ethnic Camodian                   Issarak: Cambodian independence movement/supporter

  • From 1940-45, Cambodia was administrated by France, under Japanese supervision. In 1941, the French chose Sihanouk as the next King.
  • Sihanouk grew increasingly interested in politcal participation and his royal status gave him great political influence. Keen to be seen as a moderniser, Sihanouk encouraged the formation of Cambodian political parties.
  • In 1946 the Democratic party won the first election. However, as a sign of things to come Sihanouk suppressed them as he found them too much to handle.
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  • Sihanouk considered French colonialism the best way to protect Cambodia from foreigners.
  • The Viet Minh were the most effective opponents of French colonialsim and they encouraged the Issarak.
  • The Viet Minh were motivated by the desire to:

1. Increase the number of French opponents.

2. Ensure tht the weaponry they obtained in Bangkok could be transported through Cambodia.

3. Spread Communism

  • In 1947, French Colonel Yves Gras said that there were around 1,200 armed Cambodian Issaraks (mostly Communists), supported by a similar number of Viet Minh

KPRP: Khmer People's Revolutionary Party, the Cambodian Communist Party, 1951-66

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  • In 1949, the first significant Vietnamese intervention in Cambodia occured: big units of 'Viet Minh Troops to Help Cambodia' brought the total Viet Minh force in Cambodia to 3,000.
  • The Communists despised Sihanouk, calling him 'the fascist novice' because of his young age when put on the throne by the French.
  • In September 1951, the Cambodian Communists established the KPRP. By December, it had 1,000 Khmer and 3,000 Vietnamese members.
  • The anti-colonial rebellion was brutal. Issaraks cut open the stomachs of Cambodians suspected of spying for the French, tore out their livers and ate them.
  • By early 1954, around 5,000 Cambodian Communists were fighting against the colonial government.
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Sihanouk and Cambodia Independence

  • By 1952 Sihanouk had concluded that the best way foward was to put himself at the head of the nationalist movement.
  • Independence was granted at the Geneva conference as a result of the Viet Minh defeat of the French at Dien Bien Phu.
  • The Cambodian Communists were further weakened after Geneva because many of their former supporters felt that further struggle was unnecessary as the French had been defeated.
  • Sihanouk face many great problems in the governance of independent Cambodia:

1. Some Cambodians felt he had too much power.

2. The fighting in Vietnam impacted upon Cambodia.

3. From 1967, Cambodian Communist opposition plunged Cambodia into civil war.

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Norodom Sihanouk

1941: Became King.          1954: Cambodia independence recognised at Geneva.

1954-70: Ruled Cambodia.    1970-5: Allied with Khmer Rouge against Lon Nol's government.

1975-8: Khmer Rouge puppet then prisoner.  1979-91: Allied with Khmer Rouge against Vietnamese-backed Cambodian government. 

  • Sihanouk claimed to have won independence from France, but in reality the Vietnamese drove the French out of Indochina. His Cold War neutrality policy failed to stop Cambodia suffering from the Vietnam War. His authoritarian rule helped destroy the middle ground in Cambodian politics and left the country at the mercy of extreme right-wingers such as Lon Nol and extreme left-wingers such as the Khmer Rouge.
  • Sihanouk was an influential figure in the Non-Aligned Movement, but proved unable to shield Cambodia from Cold War fallout. While undeniably a patriot, his authoritarian rule distorted independent Cambodia's political development and contrinuted to Pol Pot's brutal regime. 
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Sihanouk domestic policies

  • After Geneva, Sihanouk began silencing opposition groups through censorship, arrests and executions.
  • March 1955: He announced his abdication and consequent freedom to participate in politics as 'citizen Sihanouk'. This allowed him the traditional respect afforded a Cambodian monarch minus the ceremonial duties and limitations on his freedom his crown had necessitated. 
  • He then declared the formation of his People's Socialist Community. 
  • Sihanouk tried make his government inclusive and even brought some young leftists into the government. However, his government was undemocratic (he rigged elections in 1955) and itermittently repressive.
  • In 1960, the French ambassador wrote that Sihanouk 'is so thirsty for power that he can admit no opposition'.
  • Under Sihanouk the number of high schools rose from 8 in 1953 to 200 by 1967.
  • The peasantry failed to prosper under Sihanouk: over half were chronically in debt and between 1950 and 1970, the proportion of landless farmers rose from 4 to 20 %. Pol Pot subsequntly claimed this was a crucial factor in his rise to power. 
  • Carried out harsh and effective repression of the urban Cambodian Communist movement.
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Sihanouk foreign policy

  • Sihanouk refused to join SEATO, but accepted US military aid from May 1954. He took a leading role in the development of the new Non-Aligned Movement at the Bandung conference in April 1955 and was the first non-Communist leader to receive Chinese aid.
  • US-Cambodian relations deteriorated as the US involvement in Vietnam increased. 
  • Diem's assassination confirmed Sihanouk's belief that the Americans could not be trusted.
  • In 1964, Sihanouk dispensed American aid, expelled American citizens, and leanded towards Hanoi and Beijing.
  • In May 1965, Sihanouk broke off diplomatic relations with the US primarily because of the recent introduction of American ground troops into the Vietnam War. 
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Reasons for North Vietnamese intervention

  • The greater US involvement in Vietnam under Johnson increased North Vietnamese activity in Cambodia and destablished Sihanouk's regime:
  • Events in Vietnam damaged the government's finances, from 1965 General Westmoreland's 'search and destroy' tactics drove North Vietnamese Communist forces into Cambodia, in 1966 Sihanouk claimed that 'hundreds of our people' had been killed by American bombs.
  • The North Vietnamese intervention in Cambodia coincided with growing insurgency by Cambodian Communists led by Pol Pot.
  • CPK: Kampuchean (Cambodian) Communist Party from 1966.
  • Pol Pot and the younger generation of Cambodian Communists were anti-Vietnamese and pro-Chinese. 
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Civil War 1967-70

  • While the rebels were not a great military threat to Sihanouk's regime, they helped alter his character: the rebellion pushed the government to the right, so that Lon Nol and the Americans had greater influence. 
  • From 1967, the CPK waged war on Sihanouk's governemnt. The reasons for this Cambodian civil war were:

1. The increasing influence of the anti-Vietnamese Pol Pot and his followers within the Cambodian Communist movement.

2. Pol Pot's more militant stance was encrouaged by China.

3. The increasingly obtrusive US involvement in Cambodia. 

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Civil War 1967-70

  • The rebellion failed because:

1. Although the rebels criticised Sihanouk, telling villagers that he and Lon Nol had 'sold out their country to the United States', it proved impossible to overcome Sihanouk's prestige and nationalist credentials.

2. Sihanouk's response was ruthless: for example, some rebels were beheaded and/or disembowelled, and 40 teachers suspected of subversion were reportedly thrown off a cliff.

3. The rebel forces were not numerous: they only numbered between 2,000 and 4,000 in 1969, and around 10,000 by 1970.

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Increased US involvement

  • By 1968, Sihanouk was convinced the Communists were his greatest threat. After Sino-Cambodian relations deteriorated, Sihanouk moved to repair relations with the US. His first step was to invite Kennedy's widow to visit Cambodia's Angkor temples.
  • Sihanouk encouraged President Johnson for American anti-Communist activity in Cambodia. However, Johnson feared a Sino-Soveit reaction and confined himself to bombing the Cambodian-Vietnamese border.
  • President Nixon proved more enthusiastic about involvement in Cambodia and the result was Operation Menu in 1969: over 3,600 secret B-52 raids dropped around 160,000 tons of bombs on Cambodia between March 1969-70
  • Nixon doubled the number of reconnaissance (military observation of a region to locate an enemy) and mine-laying missions in 1969, which caused the Communists to move deeper into Cambodia and further destabilised Sihanouk's regime. 
  • The North Vietnamese responded by increased support for the Khmer Rouge
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Sihanouk's overthrow

  • By 1970, Sihanouk's regime had been destabilised from within the Khmer Rouge and by the activites of:

1. the Vietnamese Communists, who moved at will throughout the borderlands between Vietnam and Cambodia. 

2. the Saigon regime, which repressed South Vietnam's Khmer Krom minority.

3. the Americans, who responded to North Vietnamese activity in Cambodia with covert sabootage operations there (by 1970, the number of operations approached 2,000).

  • Although the Khmer Rouge began armed resistance against Sihanouk in 1967, his overthrow in March 1970 was the work of right-wingers. 
  • Sihanouk had gone to France for his annual obesity treatment. In his absence, the National Assembly replaced him with the pro-American faction led by General Lon Nol. 
  • Lon Nol: A general in the Cambodian Army, he was Prime Minister of Cambodia (1970-2) then President of the Khmer Republic (1972-5).
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Sihanouk's overthrow

Why was Sihanouk overthrown?:

1. Cambodian economy was in dire straits: Sihanouk was personally extravagant and his court was expensive.

2. While the peasantry still revered Sihanouk as a god-king, the middle class and senior military men disagreed with his policies and sought to fully align Cambodia with the United States.

3. Lon Nol knew that the mercurial Sihanouk was likely to turn on him at any time and he was encouraged in his coup by the US military and the right-wing National Assembly, which supported the overthrow by 91 votes to 1.

  • Although thousands of urbanites welcomed the overthow of the playboi prince, Lon Nol's Khmer Republic was ominously short of popular support.
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US bombing

  • During spring 1970, Cambodia appeared to be on the verge of anarchy.
  • Vietnamese residents of Cambodia were attacked both by ordinary citizens and by Lon Nol's government.
  • American bombing alientated many Cambodians yet motivated others to join the revolution.
  • With the assent of the Lon Nol regime, 30,000 US and 50,000 ARVN forces invaded Cambodia. Why?:

1. US troop withdrawals left the remaining American forces in Vietnam more vulnerable.

2. Nixon thought a Cambodian incursion would demonstrate that 'we were still serious about out commitment in Vietnam'.

3. There was great Communist activity near Phnom Penh and Nixon feared that Cambodia would 'go down the drain' unless he acted.

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Khmer Republic Fall 1970-5

  • Lon Nol's government in Phnom Penh received nearly $2 billion in American aid, but large-scale US bombing strikes aimed at the Communists destroyed large areas of Cambodian territory and killed and alientated many Cambodians.
  • The North Vietnamese Communists responded to the US/South Vietnamese invasion of Cambodia by close co-operation with the Khmer Rouge and the exiled Sihanouk.
  • By January 1971, the Communists controlled half the country: 15,000 Khmer regulars and 60,000 Khmer guerrillas fought Lon Nol's regime.
  • During 1972, the total number of Khmer rebels opposing Lon Nol rose from around 125,000 to 200,000. By 1975, they had overthrown Lon Nol's regime in a civil war in which both sides had perpetrated atrocities. 
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Pol Pot

  • 1963: Fled to the countryside to avoid Sihanouk's repression of leftists.
  • 1968: Unsuccesful rebellion against Sihanouk's regime.
  • 1970: Rebelled against Lon Nol regime.
  • 1975-9: Ruled Democratic Kampuchea.
  • As leader of Democratic Kampuchea, Pol Pot's policies were responsible for the deaths of roughly 2 million of the nation's 8 million population. Ethnic minorites and the educated were particulary targeted by the regime, which sought control, uniformity and the excision of foreign influences from Cambodia. 
  • Pol Pot's policies were a disaster for much of the Cambodian population. The international community's support for him from 1979 demonstrated how the Cold War produced strange bedfellows and could perpetuate instability within small nations. 
  • 80% of teachers and 95% of doctors were murdered under Pol Pot's regime.
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Why Khmer Republic Fell

  • In 1975, Pol Pot's Khmer Rouge forces overthrew the Khmer Republic and Pol Pot came to power. Why?:

1. The Lon Nol regime was unpopular, corrupt and incompetent military dictatorship.

2. The regime's Communist opponents were well organised, more determined and popular with the poorest Cambodian peasants who benefited from their land redistribution.

3. The Communists were supported By Sihanouk, whom the supersitious peasants still revered as a god-king.

4. Because of its involvement in Vietnam and then its intervention in Cambodia, the United States destabilised the Sihanouk and Lon Nol regimes. 

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Democratic Kampuchea 1975-8

  • In April 1975, the Communists, led by Pol Pot, established Democratic Kampuchea (DK). The Pol Pot regime aimed to make Cambodia: 

1. Free of foreigners.

2. Self sufficient in food production.

3. Great again.

  • The regime's methods included:

1. The exclusion of foreign visitors.

2. The demolition of urban life and the elvation of the social status of the poorest peasantry.

3. Mass executions. 

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Chinese models

  • The Khmer Rouge and the Chinese shared belief in: the triumph of the human will and the downgrading of intellectuals.
  • However, nationalism was more important than Communist ideology and fraternity to the Pol Pot regime, which was always anxious to emphasise its unique nature.
  • Khmer Rouge would build socialism 'without reference to any existing model' and Cambodia would go where 'no country in history has ever gone before.'
  • Pol Pot did not believe in a Mao-style personality cult. 
  • Although, Khmer Rouge beliefs may have been motivated due to pragmatic reasons and not just ideologically. E.g. collectivisation
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Evacuation to the rural areas

  • From 1973, the Khmer Rouge started evacuating urban centres in areas under their control. Troops displayed shocking behaviour to the urban residents: some drank from toilet bowls believing they were wells, others tried eating toothpaste.
  • For their part, these troops loathed the corrupted urbanites, were jealous of their wealth and resented their superior attitude and their supposed complicity in US bombing.
  • The motivation behind the evacuation was: idelological (cities were centres of capitalism), economic (Polt Pot claimed that 'a food shortage was imminent' and military (the capital was vulnerable to an invasion from nearby Vietnam).
  • The population were told they would soon be able to return, but they were forcibly resettled in the countryside and worked like slaves in agricultural labour camps.
  • Khmer Rouge superevisors forced the poorly fed relocated urbanites to work, frequently with bare hands, at planting crops and digging irrigation channels.
  • By early 1979, roughly 650,000 of these evacuees had died. 
  • Cannibalism grew rife.
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Ethnic Minorities

  • While hundreds of thousands of ethnic Khmers were executed in the Pol Pot years, proportionaly more from ethnic minorities died. The Khmer Rouge said ethnic minorities only consisted 1% of the population, but it was actually 15-20%.
  • Pol Pot viewed ethnic minorites and their different customs as a threat to uniformity.
  • The Muslim Cham was the largest ethnic minority in Cambodia. In November 1973, some Cham revolted against the Khmer Rouge attempts to make them abandon their customs and religion. They revolted again in 1975, and Pol Pot ordered 150,000 of them to be dispersed. By January 1969, roughly 100,000 of Cambodia's 250,000 Chams had been killed or worked to death.
  • Chinese Cambodians: the Khmer Rouge considered both the Cham and the Chinese diehard capitalists. Over half of them died because of Khmer Rouge policies in 1975-9. The Chinese found it hardest to adjust to peasant life, so the Khmer Rouge branded them 'lazy' and treated them harshly.
  • Vietnamese Cambodians: during 1974 under Lon Nol's regime, roughly 375,000 of the estimated 450,000 ethnic Vietnamese in Cambodia fled to Vietnam. As Vietnam was historically Cambodia's national enemy, it seems likely that they were to be victimised. 
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Pol Pot's foreign Policy

  • Pol Pot broke off diplomatic relations with the USSR and with all capitalist states in 1975, and subsequently with four Communist nations- Albania, Vietnam, Cuba and Laos.
  • Beginning in spring 1977, Cambodian-Vietnamese border clashes prompted Pol Pot to: execute those with 'Vietnamese minds in Khmer bodies', make the regime more open and tolerant in order to win more foreign and domestic support and appeal to the Chinese.
  • Deng Xiaoping (China) promised support but scolded Pol Pot humiliatingly for excessive radicalism. 
  • The purges of 'people who follow the Vietnamese' constituted in effect another Cambodian civil war that greatly weakened the Khmer Rouge.
  • Most importantly the purges contributed to the Vietnamese invasion of 1978.
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Vietnamese Invasion 1978

  • The Pol Pot regime collapsed as a result of the Vietnamese invasion of Cambodia that began on Christmas Day, 1978. Factors that motivated the invasion include:

1. The Khmer Rouge's anti-Vietnamese purge.

2. The influx of 375,000 Cambodian refugees fleeing from Pol Pot's regime into Vietnam.

3. Fear of the Sino-Cambodian alliance and the encriclement of Vietnam.

4. The desire to dominate Indochina.

  • The Vietnamese possessed one of Asia's best armies and the poorly organised Khmer Rouge forces were forced to retreat to the jungle.
  • The Vietnamese established a new Cambodian government under Heng Samrin (Vietnamese-backed leader of Cambodia from 1979-85). Pol Pot's Democratic Kampuchea now became the People's Republic of Kampuchea.
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PRK (1979-89)

A 100,000-strong Vietnamese occupation force remained in Cambodia (PRK).

The pro-Vietnamese People's Republic of Kampuchea was opposed by China, the US and ASEAN, all of which declared support for Pol Pot's deposed government and condemned Vietnam.

ASEAN: Comprising ten countries in Southeast Asia, established in 1967, which promotes political and economic co-operation.
Opponents of the PRK included 30,000 Khmer Rouge guerrillas and the KPNLF (Khmer People's National Liberation Front).
The KPNLF deployed an 8,000-strong army, led by officers of Lon Nol's army, but failed to win support of the peasantry.
A third opposition group was led by Sihanouk who joined with the KPNLF in a Coalition Government (CDGK) in June 1982These anti-Vietnamese forces received American aid.

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International Consequences:

CHINA: invaded Vietnam to demonstrate support for Pol Pot. The Chinese supported the overthrown Pol Pot because:

1. The Soviets supported Vietnam and China was worried about their expansionist ambitions.

2. The Chinese gave the Khmer Rouge forces $100 million worth of weapons each year during the 1980's.

3. The over 1 million Vietnamese of Chinese ethnicity (the 'boat people'), who fled the persecution of the Hanoi government.

  • In February 1979, the Chinese invaded Vietnam. Their aim was to teach Vietnam a lesson for having invaded Cambodia.
  • China sent 33,000 ground troops into Vietnam. Their brief incursion destroyed 6 Vietnamese missile sites and countless bridges, roads, railways. However, the Vietnamese fought well, and the Chinese suffered heavy casualities. The UN criticised the Chinese, while the Soviets supported Vietnam. 
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ASEAN/ US response

  • ASEAN: established in 1967 in order to promote economic co-operation. 
  • Its pro-Western members were Indonesia, Malaysia, the Philippines, Singapore and Thailand.
  • The Vietnamese invasion of Cambodia in 1978 strengthened its determination to co-ordinate politcal and economic policies.
  • The ASEAN issued a joint statement condemning Vietnamese intervention in Cambodia and subsequently supported opponents of Heng Samrin's regime.
  • US response: President Jimmy Carter in 1979 refered to Pol Pot as the 'worst violator of human rights in the world' but.. His representative at the United Nations condemned the Vietnamese invasion that had overthrown Pol Pot and declared the Khmer Rouge to be Cambodia's true government.
  • The US also supported Khmer Rouge possession of Cambodia's UN seat. Why? The answer lay in Carter's pro-China policy: As China was Pol Pot's ally, Carter found himself in the bizarre position of appearing to be pro-Pol Pot.
  • The Reagan administration (1981-9) supported Khmer Rouge possession of Cambodia's UN seat, and persuaded US allies to do likewise. 
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Soviet Response

  • Under Brezhnev (1964-82) the role of the USSR in Asia had increasingly become that of rival to China.
  • In 1978, Vietnam became a full member of Comecon (Soviet-dominnated economic organisation for Communist nations) and signed a Treaty of Friendship and Co-operation with the USSR.
  • As Vietnam was the only pro-Soveit state in Southeast Asia, the Soviets staunchly supported the Vietnamese and their invasion of Cambodia, sending a naval force to the Vietnamese coast and providing the Vietnamese with armaments.
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UN's role

  • In 1979, the General Assembly condemned the Vietnamese otherthrow of Pol Pot's muderous regime by 71 to 35 votes.
  • From 1979-92, the US and the People's Republic of China persuaded the UN to support Pol Pot's exiled Khmer Rouge as Cambodia's legitimate government.
  • With the Cold War over, it was easier for the great powers to agree on the future of Cambodia, and in 1989 they joined in the talks, located in Paris.
  • In March 1990, the UN Security Council proposed the formation of a new Cambodian coalition government containing representatives from all the conflicting Cambodian factions, which would hold elections supervised by a UN peacekeeping force. 
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Paris Peace Settlement

The Paris Peace Settlement (1991-3) said:

1. All competing Cambodian factions would demobilise.

2. National elections would be held in 1993.

3. The UN would administer Cambodia until the elections took place, with Sihanouk as head of state. 

  • The Khmer Rouge and Hun Sen (Vietnamese-backed leader of Cambodia from 1985) refused to demoblised their forces, so Hun Sen continued in power alongisde the UN, while Khmer Rouge guerrillas kidnapped and killed UN workers. Sihanouk declared that he had been made a puppet and retired to Beijing.
  • Regardless, elections took place in 1993 in which 90% of the electorate voted (Sihanouk won). The UN declared the election a success, and Sihanouk, Hun Sen and Ranariddh (Sihanouk's son) agreed to govern ogether. Thirs proved to be a corrupt and undemocratic government, plagued by Khmer Rouge resistance until the late 1990's. Cambdoia degenerated into anarchy again.
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