The North Vietnamese Army used Cambodia as a refuge from Vietnam, as a supply route into South Vietnam, and forced Cambodian peasants to do the Army's bidding along the Cambodian/South Vietnam border.
Money and favors to Pol Pot, the Cambodian head of state, encouraged and enabled him to extreme dictatorial powers, eventually killing millions of people opposed to his rule.
Cambodia was neutral.
During the Vietnam War, the war spilled over to Cambodia.
Being so close to Vietnam, Cambodia was able to receive the "over-flow" from it.
They were neutral.
Vietnam
It didn't, Cambodia was officially neutral.
There are large tracts of forest in Cambodia, despite the deforestation campaigns waged on Cambodia during the American(vietnam)war. During the Vietnam War, there were many forests in Cambodia, Laos and South Vietnam. Only Airmen can report on forests for North Vietnam (they're the only ones that got to observe them).
Vietnam and Cambodia
Communist control of Cambodia, Laos, and Vietnam.
Cambodia & Laos.
South Vietnam, North Vietnam, Laos, and Cambodia.
Cambodia