Family of about 130 Austroasiatic languages, spoken by more than 80 million people in South and Southeast Asia. Vietnamese has far more speakers than all other Austroasiatic languages combined. Other languages with many speakers are Muong, with about a million speakers in northern Vietnam; Khmer; Kuay (Kuy), with perhaps 800,000 speakers; and Mon, spoken by more than 800,000 people in southern Myanmar and parts of Thailand. Of all the Mon-Khmer languages, only Mon, Khmer, and Vietnamese have written traditions dating earlier than the 19th century. Old Mon, which is attested from the 7th century, was written in a script of South Asian origin that was later adapted by the Burmese (see Mon kingdom; Indic writing systems). Typical phonetic features of Mon-Khmer languages are a large vowel inventory and lack of tone distinctions.

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Khmer Rouge(French; “Red Khmer”)

Radical communist movement that ruled Cambodia from 1975 to 1979. The Khmer Rouge, under the leadership of Pol Pot, opposed the government of the popular Norodom Sihanouk. They gained support after Sihanouk was toppled by Lon Nol (1970) and after U.S. forces bombed the countryside in the early 1970s. In 1975 the Khmer Rouge ousted Lon Nol. Their extraordinarily brutal regime led to the deaths (from starvation, hardship, and execution) of one to two million people. Overthrown in 1979 by the Vietnamese, they retreated to remote areas and continued their struggle for power in Cambodia. The last Khmer Rouge guerrillas surrendered in 1998.

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Country, Southeast Asia. Area: 69,898 sq mi (181,035 sq km). Population (2005 est.): 13,327,000. Capital: Phnom Penh. The vast majority of the population belongs to the Khmer ethnic group. Language: Khmer (official). Religions: Buddhism (official); also traditional beliefs. Currency: riel. The landscape is dominated by large central plains; the Dangrek Mountains rise along the northern border. Cambodia lies largely in the basin of the Mekong River; the large lake Tonle Sap is in its western part. Much of the country is tropical forest. It is one of the world's poorest countries. Agriculture employs about three-fourths of the workforce. Cambodia is a constitutional monarchy with two legislative houses; its chief of state is the king, and its head of government is the prime minister. In the early centuries AD the area was under Hindu and, to a lesser extent, Buddhist influence. The Khmer state gradually spread in the early 8th century and reached its height under Jayavarman II and his successors in the 9th–12th centuries, when it ruled the Mekong valley and neighbouring states and built Angkor. Buddhism was widely adopted in the 13th century. From the 13th century the state was attacked by Annam and Tai (Siamese) city-states and was subject largely to Tai and Vietnamese hegemony. It became a French protectorate in 1863. It was occupied by the Japanese in World War II and became independent in 1954. Its borders were the scene of fighting in the Vietnam War from 1961, and in 1970 its northeastern and eastern areas were occupied by the North Vietnamese and penetrated by U.S. and South Vietnamese forces. A bombing campaign in Cambodia by U.S. warplanes alienated much of the population, enabling the communist Khmer Rouge under Pol Pot to seize power in 1975. Their regime of terror resulted in the deaths of at least 1.5 million Cambodians. Vietnam invaded in 1978 and drove the Khmer Rouge into the western hinterlands, but Cambodian infighting continued. A peace accord was reached by most Cambodian factions under UN auspices in 1991. Elections were held in 1993, and Norodom Sihanouk was restored to the monarchy. A civilian government slowly emerged under UN tutelage until 1997, when a coup by Hun Sen consolidated his position as prime minister. Hun Sen's party won legislative elections in 1998; also that year, Cambodia became part of ASEAN.

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• Khmer people, the ethnic group to which the great majority of Cambodians belong

See also Khmer Krom and Khmer Loeu

• Khmer language, the language of the Khmer and the official language of Cambodia
• Khmer script, the script used to write the Khmer and Khmer Loeu languages
• Khmer cuisine, the dominant cuisine in Cambodia
• Khmer Empire, which ruled much of Indochina from the 9th to the 13th centuries. (See also: Angkor)
• Khmer Rouge, a Cambodian Communist political group and guerrilla movement.
• Khmer Republic, the name of Cambodia from 1970 to 1975