Cambodia (; , or Kampuchea ), officially known as the Kingdom of Cambodia (, "Preăh Réachéanachâk Kâmpŭchéa", ), is a country located in the southern portion of the Indochina Peninsula in Southeast Asia. It is in area, bordered by Thailand to the northwest, Laos to the northeast, Vietnam to the east, and the Gulf of Thailand to the southwest. 

Cambodia has a population of over floor(/1e6) million. The official religion is Theravada Buddhism, practiced by approximately 95 percent of the population. The country's minority groups include Vietnamese, Chinese, Chams, and 30 hill tribes. The capital and largest city is Phnom Penh, the political, economic, and cultural centre of Cambodia. The kingdom is a constitutional monarchy with Norodom Sihamoni, a monarch chosen by the Royal Throne Council, as head of state. The head of government is Hun Sen, who is currently the longest serving non-royal leader in South East Asia and has ruled Cambodia for over 30 years. 

In 802 AD, Jayavarman II declared himself king, uniting the warring Khmer princes of Chenla under the name "Kambuja". This marked the beginning of the Khmer Empire which flourished for over 600 years, allowing successive kings to control and exert influence over much of Southeast Asia and accumulate immense power and wealth. The Indianized kingdom built monumental temples including Angkor Wat, now a World Heritage Site, and facilitated the spread of first Hinduism, then Buddhism to much of Southeast Asia. After the fall of Angkor to Ayutthaya in the 15th century, a reduced and weakened Cambodia was then ruled as a vassal state by its neighbours. In 1863 Cambodia became a protectorate of France which doubled the size of the country by reclaiming the north and west from Thailand.
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The country's minority groups include Vietnamese, Chinese, Chams, and 30 hill tribes.