What was the Vietnam-Cambodia War about?
The Vietnam-Cambodia War (1978–1989) was primarily Vietnam’s military intervention to end the aggressive border attacks and genocidal policies of Cambodia’s Khmer Rouge regime. The Khmer Rouge, under the leadership of Pol Pot, had launched violent cross-border raids into Vietnamese territory, killing thousands of civilians and creating an urgent threat to Vietnam’s security.
Vietnam’s objective was twofold: to stop these incursions and to overthrow the Khmer Rouge government, which had been responsible for the deaths of nearly 2 million Cambodians through mass executions, forced labor, and starvation. By invading Cambodia, Vietnam installed a new government aligned with its own communist ideals, led by the People’s Republic of Kampuchea.
Cambodia under the Khmer Rouge
Pol Pot and the rise of the Khmer Rouge
The Khmer Rouge, a radical communist movement led by Pol Pot, came to power in Cambodia in April 1975 after years of civil war. Their rise was fueled by widespread dissatisfaction with Cambodia’s monarchy and the devastation of US bombing campaigns during the Vietnam War. Pol Pot aimed to create a self-sufficient agrarian utopia, inspired by Maoist ideology but taken to extreme and brutal lengths.
The reign of terror
Upon seizing control, the Khmer Rouge immediately began implementing their radical vision by dismantling Cambodian society. Cities were evacuated, with millions forced into rural areas to work on collective farms under grueling conditions. Currency was abolished, religion outlawed, and intellectuals and professionals targeted for extermination, leading to the closure of schools, hospitals, and businesses.
Over the next four years, nearly 2 million Cambodians—about a quarter of the population—died from starvation, forced labor, torture, and mass executions. Killing fields, where victims were executed and buried in mass graves, became haunting symbols of the genocide. The Khmer Rouge regime’s paranoia led to purges within their own ranks, further destabilizing the country.
By the late 1970s, their aggressive cross-border attacks on Vietnam and genocidal policies had created a humanitarian crisis, ultimately triggering Vietnam’s intervention and the downfall of the Khmer Rouge in 1979.
What led to the Vietnam-Cambodia War?
Cross-border aggression
After coming to power, the Khmer Rouge began launching cross-border raids into Vietnam, targeting villages along the border. These attacks, marked by massacres like the 1978 Ba Chuc Massacre, where over 3,000 Vietnamese civilians were killed, posed a direct threat to Vietnam’s security and sovereignty.
Vietnam’s post-war struggles
Emerging from decades of war, Vietnam was economically fragile and focused on rebuilding. Despite its weakened state, the escalating violence from Cambodia left Vietnam with little choice but to respond. The Khmer Rouge’s aggressive actions and accusations of Vietnamese imperialism further destabilized the region, compelling Vietnam to act.
The decision to intervene
By late 1978, Vietnam determined that military intervention was the only way to protect its borders and address the humanitarian crisis caused by the Khmer Rouge. In December of that year, Vietnam launched a full-scale invasion, beginning the Vietnam-Cambodia War and aiming to remove the Khmer Rouge regime from power.
How the war was fought
Key battles and strategies
Vietnam launched its invasion of Cambodia in December 1978 with a well-organized military strategy. The campaign was swift and effective, as Vietnamese forces, supported by tanks and artillery, overwhelmed the poorly equipped Khmer Rouge. By January 7, 1979, Phnom Penh had fallen, marking the end of the Khmer Rouge’s brutal regime.
Installation of a new government
After capturing Phnom Penh, Vietnam installed the People’s Republic of Kampuchea, led by Cambodian defectors such as Heng Samrin. This Vietnam-backed government aimed to stabilize Cambodia and rebuild its shattered society, although it faced limited international recognition due to Cold War dynamics.
Guerrilla resistance
Despite losing control of the government, the Khmer Rouge retreated to the remote jungles near the Thai border. From there, they waged a guerrilla war, continuing their resistance with the support of China and covert backing from Western nations due to anti-Vietnamese sentiment during the Cold War.
Casualties and humanitarian toll
The war caused immense suffering in both Vietnam and Cambodia. Tens of thousands of soldiers and civilians were killed, and countless Cambodians were displaced, seeking refuge in camps along the Thai border. The war further strained Vietnam’s already fragile economy and deepened the humanitarian crisis in the region.
The aftermath and regional consequences
Cambodia’s recovery
After the Khmer Rouge’s fall, Cambodia struggled to rebuild under the Vietnam-backed People’s Republic of Kampuchea. While this government brought relative stability, the country remained deeply scarred by the genocide, with millions of survivors facing poverty and trauma. Vietnam’s influence in Cambodia allowed for reconstruction but also fostered resentment among some Cambodians who viewed it as foreign domination.
Vietnam’s occupation and isolation
Vietnam’s prolonged occupation of Cambodia (1979–1989) led to significant international backlash. Many Western nations and China condemned Vietnam’s actions, isolating it politically and economically. The United States and its allies, still wary of communist expansion, withheld aid and supported Cambodian resistance groups, including remnants of the Khmer Rouge.
Sino-Vietnamese War (1979)
In response to Vietnam’s invasion of Cambodia, China launched a short but bloody border war against Vietnam in early 1979. While China claimed it was punishing Vietnam, the conflict ended inconclusively, leaving tensions high between the two nations for years. This war underscored Vietnam’s precarious position, surrounded by hostile or suspicious neighbors.
Withdrawal and rehabilitation
After a decade of occupation, Vietnam withdrew its troops from Cambodia in 1989, following increasing international pressure and economic hardships at home. The United Nations played a key role in Cambodia’s rehabilitation, culminating in the 1991 Paris Peace Agreements and eventual democratic elections in 1993. While Cambodia began a slow path toward recovery, Vietnam emerged from the conflict economically drained and diplomatically isolated, needing years to rebuild its global relationships.
Sites you can visit today
Learning about the Vietnam-Cambodia War in Vietnam
- Ba Chuc Massacre Site (Mekong Delta): A haunting memorial commemorating the 3,157 Vietnamese civilians killed during a Khmer Rouge attack in 1978. The site includes preserved bones, photos, and exhibits detailing the atrocities.
- Ho Chi Minh City War Remnants Museum: While primarily focused on the Vietnam War, the museum includes sections on Vietnam’s military history, including the Vietnam-Cambodia War. It provides context on Vietnam’s intervention in Cambodia and its regional impact.
Understanding Cambodia under the Khmer Rouge
If you want to learn more about Cambodia during the Khmer Rouge era, consider visiting these significant sites in Cambodia:
- Tuol Sleng Genocide Museum (Phnom Penh): A former high school turned into a prison (S-21) by the Khmer Rouge. The museum documents the atrocities committed during Pol Pot’s regime, including haunting photographs and survivor stories.
- Choeung Ek Killing Fields (Phnom Penh): This site, where thousands of Cambodians were executed, offers a sobering insight into the genocide. Visitors can see mass graves and a memorial stupa filled with victims’ skulls, symbolizing remembrance and resilience.
These sites provide a powerful opportunity to understand the harrowing history of the Vietnam-Cambodia War and the Khmer Rouge’s devastating regime.
