Although Cambodia had achieved independence by late 1953, its military situation remained unsettled. Noncommunist factions of the Khmer Issarak had joined the government, but communist Viet Minh activities increased at the very time French Union force were stretched thin elsewhere. In April 1954, several Viet Minh battalions crossed the border into Cambodia. Royalist forces engaged them but could not force their complete withdrawal. In part, the communists were attempting to strengthen their bargaining position at the Geneva Conference that had been scheduled to begin in late April.
The Geneva Conference was attended by representatives of Cambodia, North Vietnam, the Associated State of Vietnam (the predecessor of the Republic of Vietnam, or South Vietnam), Laos, the People's Republic of China, the Soviet Union, France, Britain, and the United States. One goal of the conference was to restore a lasting peace in Indochina. The discussions on Indochina began on May 8, 1954. The North Vietnamese attempted to get representation for the resistance government that had been established in the south, but failed. On July 21, 1954, the conference reached an agreement calling for a cessation of hostilities in Indochina. With respect to Cambodia, the agreement stipulated that all Viet Minh military forces be withdrawn within ninety days and that Cambodian resistance forces be demobilized within thirty days. In a separate agreement signed by the Cambodian representative, the French and the Viet Minh agreed to withdraw all forces from Cambodian soil by October 1954.
In exchange for the withdrawal of Viet Minh forces, the communist representatives in Geneva wanted full neutrality for Cambodia and for Laos that would prevent the basing of United States military forces in these countries. On the eve of the conference's conclusion, however, the Cambodian representative, Sam Sary, insisted that, if Cambodia were to be genuinely independent, it must not be prohibited from seeking whatever military assistance it desired (Cambodia had earlier appealed to Washington for military aid). The conference accepted this point over North Vietnam's strenuous objections. In the final agreement, Cambodia accepted a watered-down neutrality, vowing not to join any military alliance "not in conformity with the principles of the Charter of the United Nations" or to allow the basing of foreign military forces on its territory "as long as its security is not threatened."
The conference agreement established the International Control Commission (officially called the International Commission for Supervision and Control) in all the Indochinese countries. Made up of representatives from Canada, Poland, and India, it supervised the cease-fire, the withdrawal of foreign troops, the release of prisoners of war, and overall compliance with the terms of the agreement. The French and most of the Viet Minh forces were withdrawn on schedule in October 1954.
Data as of December 1987