The ‘Know Your Region’ series is designed to support unit and individual professional military education on the South East Asian region. It’s important for all serving members of our military to have a foundational knowledge of the countries and issues in the Indo-Pacific.


On this page:

  • History
  • Government and Politics
  • Foreign Policy and Influences



The roots of Cambodia lie in the systemisation of wet rice agriculture and the gradual development of a more extensive political organisation that reached its zenith as the Khmer Empire (or the Angkorian Empire) which flourished for over 600 years. Most Cambodians consider themselves to be Khmers – descendants of the Empire – and cherish its most notable legacy: the Angkor Wat temple complex. Satellite imaging has revealed that Angkor, during its peak between the 10th to 13th centuries, was the largest pre-industrial urban centre in the world.

Attacks by the Tai and Cham (from present-day Thailand and Vietnam respectively) weakened the Empire, ushering in a long period of decline. In the post-Angkor period, a new Khmer capital was established at Oudong in 1618, but its monarchy was dependent on an alternating vassal relationship with the Siamese and Vietnamese for the next three centuries with only a few short-lived periods of relative independence. King Norodom placed the country under French protection in 1863, and it became part of French Indochina in 1887. Paris influenced the choice of King and maintained control over the colonial territory until young Norodom Sihanouk took the throne in 1941.

The Empire of Japan occupied the Kingdom of Cambodia for most of World War II from 1941 to the formal surrender of Tokyo in September 1945. Vichy France, who were a client state of Nazi Germany, nominally maintained the French protectorate over Cambodia and other parts of Indochina during most of the Japanese occupation. Of note are key measures taken by King Sihanouk towards Cambodia's independence supported by Tokyo. Even after the war, the French thought King Sihanouk would be easy to control. However, they were wrong and under his reign Cambodia gained independence from France on 9 November 1953. To learn more about the ancient city of Angkor, check out the video below.

The Vietnam War extended into the country in 1965 with the Ho Chi Minh Trail and establishment of the Sihanouk Trail. See the #KYR: Vietnam - Special Issue to learn more. Despite Cambodia's neutrality, the United States bombing campaign in Vietnam began in 1969 and lasted until 1973.

Following a 1970 coup d'état which installed the right-wing pro-U.S. Khmer Republic, the deposed King Sihanouk gave his support to his former enemies, the Khmer Rouge led by Pol Pot. In April 1975 – after a seven-year struggle – these communist forces captured Phnom Penh and evacuated all cities and towns. At least 1.5 million Cambodians died from execution, forced hardships, or starvation during the Khmer Rouge regime under Pol Pot. A December 1978 Vietnamese invasion drove the Khmer Rouge into the countryside, began a ten-year Vietnamese occupation, and touched off 20 years of civil war. For more information about the regime and its legacy, see the #KYR: Cambodia - Special Issue.

The 1991 Paris Peace Accords mandated democratic elections and a cease-fire, which was not fully respected by the Khmer Rouge. United Nations (UN) sponsored elections in 1993 helped restore some semblance of normalcy under a coalition Government. Also that year, the monarchy was restored with Norodom Sihanouk reinstated as King. To get an overview of Cambodia’s entire history, watch the following video.

As a small nation between Vietnam and Thailand, the Kingdom of Cambodia has a complex relationship with its neighbours due to its violent past. A century of non-ending conflict which saw European colonisation, a U.S. bombing campaign, and the rise of the Khmer rouge, all nearly eradicated Cambodia from existence. Ironically, the country was rescued by its ancient nemesis, Vietnam, when they invaded Cambodia and removed the Khmer Rouge from power. Even now – after decades of somewhat stability – Cambodia is still recovering from its past.

Access the following resources and visit the Tourism of Cambodia website for more information on Cambodian history.


Government and Politics

The Kingdom is an elective constitutional monarchy with a King, currently Norodom Sihamoni, chosen by the Royal Council of the Throne as head of state. The head of Government is the Prime Minister, currently Hun Sen, the longest serving non-royal leader in Southeast Asia, having ruled since 1985. The Prime Minister is appointed by the King on the advice and approval of the National Assembly. The Prime Minister and the ministerial appointees exercise executive power.

Legislative powers are shared by the executive and the bicameral Parliament of Cambodia (sâphéa tâmnang réastrâ), which consists of a lower house, the National Assembly (rôdthâsâphéa) and an upper house, the Senate (prœ̆tthôsâphéa). Members of the 123-seat Assembly are elected through a system of proportional representation and serve for a maximum term of five years. The Senate has 61 seats, two of which are appointed by the King and two others by the National Assembly, and the rest elected by the commune councillors from 24 provinces of Cambodia. Senators serve six-year terms.

On 14 October 2004, King Norodom Sihamoni was selected by a special nine-member Royal Throne Council, part of a selection process that was quickly put in place after the abdication of King Sihanouk a week prior. Sihamoni's selection was endorsed by Prime Minister Hun Sen and National Assembly Speaker Prince Norodom Ranariddh (the King's half-brother and current chief advisor), both members of the throne council. He was enthroned in the capital, Phnom Penh, on 29 October 2004.

The highest courts in the Kingdom are the Supreme Council and Constitutional Court, other courts include the Appellate Court, provincial and municipal courts, and the Military Court. In 1997, the Cambodian Government requested UN assistance in establishing trials to prosecute former Khmer Rouge senior leaders for crimes against humanity committed during the 1975-1979 Khmer Rouge regime. The Extraordinary Chambers of the Courts of Cambodia (ECCC, also called the Khmer Rouge Tribunal) was established in 2006 and began hearings for the first case in 2009 with court proceedings ongoing. Watch the following video to learn more about Cambodia’s political system.

Since the UN-sponsored elections in May 1993, Cambodia has been engaged in a process of attempted recovery and improving the running of democratic elections. With the presence of independent observers, progress has been made but substantial problems remain.

Elections in July 2003 were relatively peaceful, but it took one year of negotiations between contending political parties before a coalition government was formed. Local (Commune Council) elections were held in Cambodia in 2012, with little of the violence that preceded prior elections. National elections in July 2013 were disputed, with the opposition – the Cambodia National Rescue Party (CNRP) – boycotting the National Assembly. The political impasse was ended nearly a year later, with the CNRP agreeing to enter parliament in exchange for commitments by the ruling Cambodian People’s Party (CPP) to undertake electoral and legislative reforms.

The CNRP made further gains in local commune elections in June 2017, accelerating sitting Prime Minister Hun Sen's efforts to marginalise the CNRP before national elections in 2018. Hun Sen arrested CNRP President Kem Sokha in September 2017. The Supreme Court dissolved the CNRP in November 2017 and banned its leaders from participating in politics for at least five years. The CNRP’s seats in the National Assembly were redistributed to smaller, less influential opposition parties, while all of the CNRP’s 5,007 seats in the Commune Councils throughout the country were reallocated to the CPP. With the CNRP banned, the CPP swept the 2018 national elections, winning all 125 National Assembly seats and effectively turning the country into a one-party state. To learn more about the elections in 2018, watch the report by Now This World to answer the question: how corrupt was Cambodia’s elections?

While officially a multiparty democracy, Cambodia has shifted from a flawed but improving multiparty democracy with an independent media and vibrant civil society to a de facto one-party state intolerant of dissent.

Hun Sen is a Cambodian politician and former military commander in the Khmer Rouge army who has served as the Prime Minister of Cambodia since 1985. He is president of the Cambodian People's Party (CPP), has been a prominent communist, Marxist–Leninist and is now a part of free-market capitalist and national conservative political parties. Although Khmer nationalism has been a consistent trait of all of them, he is thought to lack a core political ideology. In foreign policy, Sen has in recent years strengthened a close diplomatic and economic alliance with China, who have undertaken large-scale infrastructure projects and investments in Cambodia under the Belt and Road Initiative. Meanwhile, Sen has frequently criticised Western powers in response to their sanctions on Cambodia over human rights issues and has overseen a number of diplomatic disputes with neighbours. Cambodia is consistently listed on the Corruption Perceptions Index by Transparency International as one of the most corrupt Governments in the world, currently at 21 out of 100.

The global COVID-19 pandemic spread to Cambodia in early 2020. Despite minimising the disease's spread for much of the first year, the country's health system was put under strain by a major outbreak in early 2021 which prompted several lockdowns. It also had a severe economic impact, with the tourism industry particularly affected due to international travel restrictions. Watch the following report by Al Jazeera on the current status of the CRNP, then access the following resources to learn more about Cambodia’s government.


Foreign Policy and Influences

The foreign relations of Cambodia are handled by the Ministry of Foreign Affairs and International Cooperation (MFAIC) under Prak Sokhon. The Government ministry is responsible for representing the Kingdom to the international community as it fulfils its role to oversee foreign relations, maintain diplomatic missions in other countries, and provide visa services. Cambodia has established diplomatic relations with numerous countries. MFAIC reports twenty embassies in the country including many of its Asian neighbours and those of important players during the Paris peace negotiations; including the U.S., Australia, Canada, China, the European Union, Japan, and Russia. As a result of its international relations, various non-government organisations have assisted with social, economic, and civil infrastructure needs. Cambodia relies heavily on foreign aid and so MFAIC has established a clear Economic Diplomacy Strategy 2021-2023.

The Kingdom of Cambodia pursues a foreign policy that protects and promotes its national interests by undertaking the following five tasks:

  1. Protect national independence, sovereignty, territorial integrity and neutrality; maintain peace, security, stability, order, and social unity.
  2. Foster more friendship abroad based on the spirit of national independence.
  3. Promote economic diplomacy.
  4. Continue to support and strengthen multilateralism.
  5. Enhance the quality, efficiency and capacity of Cambodian diplomats.

However, the country is still a minor power in the region. With a comprehensive power score of 7.3 out of 100 on the 2020 Edition of the Lowy Institute Asia Power Index. Watch the Prime Minister Sen’s virtual address to the United Nations General Assembly to learn about the Kingdom’s current outlook and strategic vision for the future.

One of the key challenges in Cambodia’s foreign policy will be in the area of neighbourhood diplomacy. While the violent ruptures of the 1970s and 1980s have passed, several border disputes between Cambodia and its neighbours persist. There are disagreements over some offshore islands and sections of the boundary with Vietnam and undefined maritime boundaries. Cambodia and Thailand also have border disputes, with troops clashing over land immediately adjacent to the Preah Vihear temple in 2011, leading to a deterioration in relations. In 1962, an International Court of Justice decision awarded the boundary in Cambodia's favour but the situation remains unsettled. Additionally, the Kingdom is concerned about Laos' extensive upstream dam construction.

Signifying its regional integration, the Kingdom of Cambodia became the last member of the Association of Southeast Asian Nations (ASEAN) in April 1999. Since then, Cambodia has chaired ASEAN twice, the first time in 2002 and the second time in 2012. Next year the Kingdom will Chair ASEAN for the third time. It is an opportunity to shape regional diplomacy and promote meaningful dialogue. The MFAIC has vowed to enhance the bloc's centrality, unity, and development in all fields while building resilience against rising geo-political competition, transnational crime, terrorism, climate change, and infectious diseases. At the handover ceremony, Prime Minister Sen said, "As the chair of ASEAN in 2022, Cambodia will steer ASEAN's collective efforts to accomplish our important tasks, especially expediting the building process of an equitable, strong, and inclusive ASEAN Community." Ultimately, Cambodia is embracing a diversification strategy: maximising friends while minimising antagonists. To hear from Prince Norodom, a royal politician who previously served as Minister for Foreign Affairs, check out the next video.

Since 1997, China began developing closer relations with Prime Minister Sen. At least 26% of Cambodia's total trade goes by China. In the last decade, large sums of Chinese investments have been channelled into the capital, with suggestion that top Cambodian officials have benefited from the foreign investment. Considering the poor position of Cambodia, its policymakers believe they have no choice but to continue their patron-client relationship with China. The CPP also partly sees their large northern neighbour's support as a counterbalance to Thailand, Vietnam, and international criticism of the CPP’s human rights and anti-democratic record.

In the 2010s, Phnom Pehn and Beijing cultivated deeper ties. Under a Comprehensive Partnership of Cooperation signed in 2006, ties have expanded to include vast economic investments, infrastructure loans, and extensive military aid. Trade between Cambodia and China jumped from US$732 million in 2006 to US$4.8 billion in 2016. China's dominant participation in Cambodia's economy, its influence over Cambodian politics, and the influx of Chinese immigrants have raised anti-Chinese sentiment. Despite Hun Sen’s insistence of the Kingdom’s sovereign autonomy, the considerable amount of aid should not be underestimated.

More recently, the 'Action Plan 2019-2023 on Building China-Cambodia Community of Shared Future' committed the two countries to undertake 31 measures in the five domains of politics, security, economics, people-to-people relations, and multilateral cooperation. It also agreed to promote ties between China and ASEAN by building a shared future in the region more generally.

To learn more about Cambodia’s foreign relations and position in regional forums, explore the following resources.


Discussion Questions:

  1. Cambodia has been heavily engaging economically with China in recent times and is a signatory to the belt and road initiative. Considering Cambodia’s history which has seen it flirt with communism, is there a risk that the nation may be seduced by Chinese economics and ideology? How will that influence its relations with regional partners, especially Australia?
  2. Over 1000 ADF troops served in Cambodia under the UNTAC peacekeeping efforts in the early 1990’s. Is Cambodia’s relationship with Australia a strong one, based on historical interaction, or is Cambodia a lesser regional partner? What opportunities are there for the two nations to interact from a diplomatic perspective?
  3. Cambodia is heavily reliant on foreign aid, and has relationships of various depths with western, Asian, and eastern European nations. What strategic significance does Cambodia hold (from a diplomatic, economic, and military perspective)? How should this influence Australia’s foreign policy approach towards Cambodia and her immediate neighbours?
  4. Vietnam and Cambodia have a violent and tragic history, which shifted somewhat when Vietnam invaded in order to remove the Khmer Rouge forces in the late 70’s. As Vietnam continues to rise in regional influence, what role can it play in assisting Cambodia develop without unnecessary influence and interference from China? What role should Australia play in helping Cambodia develop its international relationships?