Following the independence of both countries, the Philippines under President Ramon Magsaysay established official contact with South Vietnam in 1954.

The contingent initially consisted of 16 individuals who were doctors, nurses, technicians, and civic action officers from the Armed Forces of the Philippines.

Aside from humanitarian aid, the contingent was also involved in psychological warfare according to the official records of the United States' Military Assistance Command, Vietnam.

[4] On April 14, 1965, Prime Minister Phan Huy Quát sent a letter to the Philippine President stating South Vietnam's dire need for military assistance.

[1][5] Under Marcos he did not allow the United States to fully fund the formation of the contingent since he believed the Filipinos would be treated as mercenaries by the Americans if they did so.

The South Vietnam government accepted the Philippines offer of a second contingent on August 15, 1966 while PHILCAG commander, General Gaudencio V. Tobias receiving order from Marcos to secretly establish contact with the Viet Cong so that the Philippines could act as an intermediary for a peace negotiation since there is a belief in the country that North Vietnam would not be hostile to idea due to PHILCAG's non-combat role in the war.

[4] The Philippines hosted the Manila Summit of the Southeast Asia Treaty Organization in October 1966, where seven members promised aid to South Vietnam against the communist North.

There was some opposition regarding the deployment of the Philippine Civic Action Group to South Vietnam by academics, students, and laborers who held protests during the summit.

On December 1, the permanent chancery was opened at 1 Rue Aux Fluera, across the present day Bitexco Financial Tower, with Amb.

[1] South Vietnam as well established an embassy in Manila with the Chief Minister Cao Thai Bao heading the mission.

The Philippine Embassy to South Vietnam was permanently closed on April 29, 1975 a day before Saigon fell to the North Vietnamese forces.

It was reported that South Vietnam sent prostitutes to the Filipino soldiers' commanding officers' party to lure them out of Southwest Cay.