The French.
China, France, Japan...then the Vietnam War involving the US.
Indochina
France. Long before that the area now known as Vietnam was part of the Khmer Empire, the remnant of which is now known as Cambodia.
Yes, the Chinese ruled Vietnam for 1,000 years until 939 AD, China was defeated by Vietnam and had lost control over Vietnam. Vietnamese soldiers and civilians in Vietnam were ruled by chinese soldiers and then finally the vietnamese soldiers fought back against the chinese soldiers and China lost the significant battle against Vietnam.
Vietnam was split into two countries during the vietnam war, the north was ruled by Ho Chi Minh and the South by Ngo Diem.
Cambodia and Vietnam.
France
France
Hung Vuong's Dynasty ruled Vietnam from 2897 BC to 258 BC.
Prince Shihanok ruled Cambodia during the initial of Vietnam War. Because he allowed North Vietnamese to use Cambodian road as transportation, the US helped Lon Nol to overthrow Prince Shikanok and became the prime minister of Cambodia.
Vietnam and Laos. North Korea and China are also communist but are not in South-East Asia.