Kingdom of Cambodia (1953–1970) in the context of "New Khmer Architecture"

The Cambodian Civil War (Khmer: សង្គ្រាមស៊ីវិលកម្ពុជា, UNGEGN: Sângkréam Sivĭl Kâmpŭchéa) was a civil war in Cambodia fought between the Khmer Rouge, supported by North Vietnam and China, against the government of the Kingdom of Cambodia and, after October 1970, the Khmer Republic, which had succeeded the kingdom after a coup, both supported by the United States and South Vietnam. The conflict was part of the Vietnam War.

The conflict was linked to the Vietnam War. The North Vietnamese People's Army of Vietnam (PAVN) was involved to protect its bases in eastern Cambodia, which were crucial to its military effort in South Vietnam. This presence was initially tolerated by Prince Norodom Sihanouk, the Cambodian head of state, but domestic resistance combined with China and North Vietnam aiding the anti-government Khmer Rouge caused him to request help from the Soviet Union to stop this.

Norodom Sihanouk (/ˈsiː.ənʊk/; 31 October 1922 – 15 October 2012) was a member of the House of Norodom who led Cambodia as King, Chief of State and Prime Minister. He is known as Samdech Euv (meaning "King Father"). During his lifetime, Cambodia was under various regimes, from French colonial rule (until 1953), a Japanese puppet state (1945), an independent kingdom (1953–1970), a military republic (1970–1975), the Khmer Rouge regime (1975–1979), a Vietnamese-backed communist regime (1979–1989), a transitional communist regime (1989–1993) to eventually another kingdom (since 1993).

Sihanouk was the only child of Prince Norodom Suramarit and Princess Sisowath Kossamak, daughter of King Sisowath Monivong. When his grandfather Monivong died in 1941, Sihanouk became king amidst French colonial rule. After the Japanese occupation of Cambodia during World War II, he secured Cambodian independence from France in 1953. He abdicated in 1955 and was succeeded by his father, Suramarit, so as to directly participate in politics. Sihanouk's political organization Sangkum won the general elections that year, and he became prime minister of Cambodia. He governed the country under one-party rule and suppressed political dissent. After his father died in 1960, Sihanouk assumed a new position as Chief of State of Cambodia.

The Geneva Conference was intended to settle outstanding issues resulting from the Korean War and the First Indochina War and involved several nations. It took place in Geneva, Switzerland, from 26 April to 21 July 1954. The part of the conference on the Korean question ended without adopting any declarations or proposals and so is generally considered less relevant. On the other hand, the Geneva Accords that dealt with the dismantling of French Indochina proved to have long-lasting repercussions.

Diplomats from South Korea, North Korea, China, the Soviet Union, and the United States dealt with the Korean side of the conference. On the Indochina issue, the conference involved representatives from France, China, the Soviet Union, the United States, the United Kingdom, the Democratic Republic of Vietnam, the State of Vietnam, the Kingdom of Laos, and the Kingdom of Cambodia. Three binding ceasefire agreements about Indochina ended hostilities in Vietnam, Laos, and Cambodia. The Pathet Lao were confined to two provinces in northern Laos, and Khmer Issarak forces disbanded. Vietnam was provisionally partitioned at the 17th parallel, with troops and personnel of the Democratic Republic of Vietnam regrouping to the North, and those of the State of Vietnam and French Union regrouping to the South. Alongside them, a non‑legally binding Final Declaration called for international supervision (via the International Control Commission), prohibited the introduction of foreign troops and bases in Vietnam, affirmed that the 17th parallel was only a provisional demarcation, and scheduled national elections for 1956. Worsening relations between the communist and anti-communist sides would eventually lead to the Vietnam War. As such, historians generally regard the Geneva Conference as failing to secure lasting peace in Indochina.