After a long series of wars with neighbouring kingdoms, Angkor was sacked by the Thai and abandoned in 1432 because of ecological failure and infrastructure breakdown.[15][
In 1863, King Norodom, who had been installed by Thailand,[17]
Cambodia continued as a protectorate of France from 1863 to 1953, administered as part of the colony of French Indochina, though occupied by the Japanese empire from 1941 to 1945[citation needed]. Cambodia gained independence from France on November 9, 1953. It became a constitutional monarchy under King Norodom Sihanouk. When French Indochina was given independence, Cambodia lost official control over the Mekong Delta as it was awarded to Vietnam.
In 1955, Sihanouk abdicated in favour of his father in order to be elected Prime Minister. Upon his father's death in 1960, Sihanouk again became head of state, taking the title of Prince. As the Vietnam War progressed, Sihanouk adopted an official policy of neutrality in the Cold War. However, Cambodians began to take sides, and he was ousted in 1970 by a military coup led by Prime Minister General Lon Nol and Prince Sisowath Sirik Matak, while on a trip abroad. From Beijing, Sihanouk realigned himself with the communist Khmer Rouge rebels who had been slowly gaining territory in the remote mountain regions and urged his followers to help in overthrowing the pro-United States government of Lon Nol, hastening the onset of civil war.[18]
Between 1969 and 1973, U.S. forces bombed and briefly invaded Cambodia in an effort to disrupt the Viet Cong and Khmer Rouge.[19] Some two million Cambodians were made refugees by the war and fled to Phnom Penh. Estimates of the number of Cambodians killed during the bombing campaigns vary widely, as do views of the effects of the bombing. The US Seventh Air Force argued that the bombing prevented the fall of Phnom Penh in 1973 by killing 16,000 of 25,500 Khmer Rouge fighters besieging the city.[20] However, journalist William Shawcross and Cambodia specialists Milton Osborne, David P. Chandler and Ben Kiernan argued that the bombing drove peasants to join the Khmer Rouge.[21] Cambodia specialist Craig Etcheson argued that the Khmer Rouge "would have won anyway", even without US intervention driving recruitment.[
As the war ended, a draft US AID report observed that the country faced famine in 1975, with 75% of its draft animals destroyed, and that rice planting for the next harvest would have to be done "by the hard labour of seriously malnourished people". The report predicted that
without large-scale external food and equipment assistance there will be widespread starvation between now and next February ... Slave labour and starvation rations for half the nation's people (probably heaviest among those who supported the republic) will be a cruel necessity for this year, and general deprivation and suffering will stretch over the next two or three years before Cambodia can get back to rice self-sufficiency.[
Stupa which houses the skulls of those killed at Choeung EkThe Khmer Rouge reached Phnom Penh and took power in 1975. The regime, led by Pol Pot, changed the official name of the country to Democratic Kampuchea, and was heavily influenced and backed by China. They immediately evacuated the cities and sent the entire population on forced marches to rural work projects. They attempted to rebuild the country's agriculture on the model of the 11th century, discarded Western medicine, and destroyed temples, libraries, and anything considered Western. Over a million Cambodians, out of a total population of 8 million, died from executions, overwork, starvation and disease.[24]
Estimates as to how many people were killed by the Khmer Rouge regime range from approximately one to three million.[25][
In November 1978, Vietnam invaded Cambodia to stop Khmer Rouge incursions across the border and the genocide in Cambodia.[28]
In recent years, reconstruction efforts have progressed and some political stability has finally returned. However, Cambodia's natural resources, particularly its valuable timber, are still being exploited by interests from Thailand, Vietnam, Malaysia, Singapore and Australia. Until 1999, the Khmer Rouge were still active in some areas, often supporting illegal timber operations. At that time, travel by land and river was still precarious.[
The stability established following the conflict was shaken in 1997 by a coup d'état,[31]



