Originally a civil servant in the French colonial administration of Laos, he joined the resistance movement against the Japanese occupiers during the last year of World War II.
He would be temporarily removed from power during an August 1960 coup by Captain Kong Le, only to return with a Central Intelligence Agency backed counter-coup in December.
His American backers periodically curtailed military aid to his forces to compel his compliance, even as the Royal Lao Army's performance deteriorated.
As World War II wound down in 1945, he joined the resistance movement opposed to the Japanese occupation of Laos.
In 1950, he joined the nascent Laotian National Army (Armee Nationale Laotienne)[1] and served as a military adviser at the 1954 Geneva Conference.
[1] Under Colonel Phoumi, there was a massive appointment of military officers subordinate to him into command positions in the Royal Lao Army.
[11] Phoumi returned from France to command the newly created Military Region 5; he added the political post of Deputy Minister for Internal Security.
[1] On 4 September 1959, the Royal Lao Government appealed to the United Nations for an intervention against invasion by North Vietnamese communists.
Also, on 7 September, Phoui proclaimed martial law even as his government insisted that "foreign invaders" had vacated Houaphanh Province.
As the Laotian crisis began to gather skeptical coverage in the international press, Phoumi flew to Bangkok for a four-day visit.
He advised the Royal Lao Government that its policy should be strictly neutral if it is expected to receive support from the United Nations.
On 25 December, General Phoumi took charge of the government in a bloodless coup, using Captain Kong Le and his 2nd Parachute Battalion (2e Bataillon de Parachutistes) to occupy Vientiane's infrastructure.
To bolster Phoumi's forces, Operation Millpond was founded to secretively import American air power on the Royal Lao Government's side.
He also promoted himself to Major general and began construction of a downtown monument in Vientiane celebrating his victory in the battle for control of the city.
[26] The International Control Commission established by the 1954 Geneva Conference was renewed and engineered a truce on 11 May 1961, while the details of a new Lao government could be settled.
[32] In late December, Phoumi accused the United States of a "defeatist policy", and of treating the Royal Lao Government "like a small child".
On 25 March 1962, Phoumi, W. Averell Harriman, and Field Marshal Sarit Thanarat met in Nong Khai, Thailand.
Sarit, who was kin to Phoumi, tried to convince him to join a coalition that split control of the military and police on three ways among the Royalists, Neutralists, and the Pathet Lao.
Phoumi directed his troops into the ensuing Battle of Luang Namtha in the beliefs that the possession of that border town could be settled by military means, and that his American backers would be forced to support his actions.
[34][35][36] Phoumi turned to a secretive source of income by deputizing General Ouane Rattikone to trade opium to generate the needed military funding.
After the Luang Namtha defeat, U.S. President John F. Kennedy wanted Phoumi out of politics, and strictly limited to a military role.
President Kennedy directed Ambassador Winthrop G. Brown to make it known to Vientiane's politico-military elite that Phoumi no longer had the confidence of the U.S. for his political actions.
Despite the American acceptance of the FAN as allies,[42] by 18 May 1963, Ambassador Leonard Unger performed a re-examination of Royalist forces.
Because of their poor combat performance, Unger thought the Royal Lao Army and FAN would serve only to warn the government of communist attacks without offering significant resistance.
With U.S. State Department consent, the RLAF was strengthened by swapping in T-28s for worn-out T-6 Harvards on a one-to-one basis so the International Agreement was not breached.
Phoumi found himself at odds with his American backers, who believed that an advance that would almost reach the border of the Democratic Republic of Vietnam would outrun supplies while inviting Vietnamese retaliation.
When Phoumi did launch the assault, the ensuing Battle of Lak Sao would indeed end with the Royal Lao Army and its Neutralist allies dispersed in disarray by enemy counterattacks.
[45] On 18 April 1964, General Siho Lamphouthicoul, who had aided Phoumi's return to power in December 1960, sent his Directorate of National Coordination police to secure the streets of Vientiane.
[50][51] Phoumi convinced a loyal subordinate to return to Vientiane and retrieve a cache of gold, which he used to settle into a comfortable retirement in Songkhla, Thailand.
Now that he was in exile, Kouprasith Abhay, Ouane Rattikone, and Oudone Sananikone began conspiring to diminish Thao Ma's command; this led to the latter's 1966 coup.