Cambodia (Kampuchea) is the remnant of the old Khmer kingdom which once included the Mekong delta. It was a French protectorate from 1863 until 1953. Unlike Laos, it has no border mountains separating it from Vietnam; some Vietnamese settled in Cambodia, although there was an old antagonism between the two neighbours. During the 1960s, Cambodia tried to keep out of the Vietnamese conﬂict, turning a blind eye to the way North Vietnamese troops were sent along the ‘Ho Chi Minh trail’ through Laos and eastern Cambodia to ﬁght in South Vietnam (61); but in 1970 Cambodia itself became a battleﬁeld. Its communist guerrillas, called the Khmers Rouges (‘Red Khmers’), got the upper hand
Phnom Penh, backed by 150,000 Vietnamese troops. More Cambodians ﬂed to Thailand; others got only as far as refugee camps along the Thai border, which were mostly controlled by Khmer Rouge guerrillas.