Cambodia, formally the Kingdom of Cambodia, is a Southeast Asian nation situated in the southern part of the Indochinese Peninsula. It has an area of 181,035 square kilometers (69,898 square miles), with Thailand to the northwest, Laos to the north, Vietnam to the east, and the Gulf of Thailand to the southwest. Cambodia has a two-season tropical monsoon climate, and the nation is made up of a central floodplain centered on the Tonle Sap Lake and the Mekong Delta, bordered by hilly areas. Phnom Penh is the capital and biggest city.
Cambodia is a sovereign state with a population of around 17 million people. Buddhism is the official state religion, as stated in the constitution, and is practiced by more than 97 percent of the people. Vietnamese, Chinese, Chams, and 30 hill tribes are among Cambodia's minority groups. Phnom Penh, Cambodia's capital and biggest city, serves as the country's political, economic, and cultural hub. The kingdom is an elected constitutional monarchy with a monarch, presently Norodom Sihamoni, chosen as head of state by the Royal Council of the Throne. The Prime Minister, now Hun Sen, is the longest-serving non-royal leader in Southeast Asia, having reigned since 1985.
The Cambodian area has been populated since ancient times. Jayavarman II crowned himself king in 802 AD, unifying the warring Khmer lords of Chenla under the banner of "Kambuja." This was the start of the Khmer Empire, which lasted over 600 years. The Indianised empire aided the expansion of Hinduism and eventually Buddhism over most of Southeast Asia, as well as undertaking several religious infrastructure projects. The most renowned of these temples is Angkor Wat, which is a World Heritage Site. Cambodia's authority declined in the fifteenth century, while its rivals Vietnam and Thailand gained stronger. Cambodia became a French protectorate in 1863 and eventually became part of French Indochina.
Cambodia obtained independence from France in 1953, after a period of Japanese rule during WWII. Despite Cambodia's neutrality, the Vietnam War entered the nation along the Ho Chi Minh and Sihanouk trails in 1965. A coup in 1970 established the US-aligned Khmer Republic, which was toppled by the Khmer Rouge in 1975. From 1975 to 1979, the Khmer Rouge governed Cambodia and committed atrocities. They were deposed in the Cambodian–Vietnamese War. The de facto government became the Vietnamese-occupied People's Republic of Kampuchea, with efforts to reconstruct the country after the massacre hampered by little international recognition and continuous fighting.
Cambodia was temporarily ruled by a United Nations mission (1992–93) after the 1991 Paris Peace Accords, which effectively ended the conflict with Vietnam. The UN withdrew following elections in which around 90% of registered citizens voted. The 1997 coup solidified control under Prime Minister Hun Sen and the Cambodian People's Party, which still holds power today.
Cambodia is classified as a least developed nation by the United Nations. Cambodia is a member of the United Nations, ASEAN, the Regional Comprehensive Economic Partnership, the East Asia Summit, the World Trade Organization, the Non-Aligned Movement, and La Francophonie. Although Cambodia is a multi-party state by constitution, the political system is centered on a single political party, the Cambodian People's Party. While Cambodia's per capita income remains low in comparison to other surrounding nations, the country boasts one of Asia's fastest-growing economies. Agriculture continues to be the most important economic sector, with substantial development in textiles, building, clothing, and tourism contributing to greater foreign investment and international commerce. Cambodia, which is rich in biodiversity and seasonal tropical forests, has a high rate of deforestation and is regarded as one of the most susceptible nations to climate change. Corruption, poverty, and human rights have been identified as important challenges in the nation by foreign observers.