Opposed to all forms of Vietnamese rule, FULRO fought against both sides in the Vietnam War against the Soviet-aligned North (including the Vietcong) and the American-aligned South at the same time.

FULRO's primary supporter during the 1960s and early 1970s conflict in Southeast Asia was Cambodia (under former monarch and then head of state, Prince Norodom Sihanouk), with some aid sent by the People's Republic of China during the period of the Third Indochina War.

[3] After 1963, Y Bham Enuol then remained exiled in Cambodia for the rest of the war, while former co-founder of the parent BAJARAKA, left-leaned Y Bih Aleo, became the Vice President of the National Liberation Front of South Vietnam (NLF) and leader of the Viet Cong's Montagnard Autonomy Movement in 1961.

[4] The FULRO organized two Montagnard uprisings among the ranks of US-trained local CIDGs in September 1964 and December 1965, both were violently repressed by the South Vietnamese Army (ARVN).

"[7][8] For centuries, Vietnamese rulers had expanded their domains southward, conquering Khmer and Cham territory as part of the Nam tiến (March to the South) and then colonizing it militarily under the đồn điền (plantation) system.

Son Ngoc Thanh in 1958, and the Kaingsaing Sar, or Khmer White Scarves movement, a semi-mystic, semi-military group, founded in 1959 by a monk, Samouk Seng.

[13] The South Vietnamese government persisted with its "Social and Economic Council for the Southern Highlands" without making any provision for local autonomy, claiming that these communities needed to be "developed" as they were "poor" and "ignorant".

[14] On May 1, 1958, a group of intellectuals, headed by a French-educated Rhade (Ê Đê) civil servant, Y Bham Enuol, established an organization seeking greater autonomy for the minorities of the Vietnamese Central Highlands.

The organization was given the name BAJARAKA, which stood for four main ethnic groups: the Bahnar (Ba Na), the Jarai, the Rhade, and the Koho (Cơ Ho).

In 1965, FULRO released maps showing that their ultimate goal was for Montagnard and Cham independence within a revived new Champa state and for Khmers to retake Cochinchina.

Several Vietnamese soldiers were killed and the Americans disarmed, and FULRO activists from the Buon Sar Pa base seized the radio station on Route 14 on the south-west outskirts of Buôn Ma Thuột, from which they broadcast calls for independence.

[25] During the morning of September 21, Y Bham Enuol was quickly abducted from his residence in Buôn Ma Thuột by elements from the Buon Sar Pa group and communiques were issued in his name.

[25] Several weeks later, Y Bham's family were quietly taken from his village, Buon Ea Bong, three kilometres northwest of Buôn Ma Thuột, and escorted into the FULRO base in Cambodia's Mondulkiri Province.

An official surrender ceremony took place in the mostly deserted Buon Sar Pa base; however this resulted in a loss of face for those dissident Montagnards who had agreed to stand down and await the promises made by General Co during negotiations with their leaders on the night of September 21, 1964.

[28] At the time of the revolt, Y Bun Sur and Les Kosem were senior officers serving in the Royal Khmer Army and both were also agents of Cambodia's 12th Bureau, the country's secret intelligence service.

When the Khánh regime collapsed in June 1965, the administration under new Prime Minister of South Vietnam Nguyễn Cao Kỳ terminated the state's discriminatory development programs to appease the tensions with the indigenous peoples.

The South Vietnamese government sent a diplomatic contingent to Buôn Mê Thuột in August 1968 to negotiate with FULRO representatives, including Y Bham, after a promise of safe conduct was given to him by Prime Minister Trần Văn Hương.

On December 30, 1968, Kosem, at the head of several battalions of the Royal Cambodian Army, and accompanied by a group from the militant FULRO wing responsible for the 1965 fighting, surrounded and took Camp le Rolland.

Enuol was placed under effective house arrest in Phnom Penh at the residence of Colonel Um Savuth of the Cambodian army, where he was to remain for the next six years.

These disparate armed groups looked forward to the collapse of the Saigon regime and had some local cooperation with the Viet Cong, who offered unofficial support such as caring for their wounded.

[33] Lon Nol backed FULRO hill tribes, fighting a proxy war against the NLF via Khmer Krom detachments in South Vietnam and Cambodia's frontier region, as he desired to emulate Van Pao.

Y Bham, Y Bun Sur, and some 150 members of the militant FULRO faction were, at the time, under house arrest in the compound of Colonel Um Savuth of the Khmer Army located near Pochentong Airport.

Several thousand FULRO troops under Brigadier General Y Ghok Nie Krieng carried on fighting the Vietnamese forces, but the promised American aid did not materialize.

FULRO continued operations in the remote highlands throughout the late 1970s and into the early 1980s, but it was increasingly weakened by internal divisions, and trapped in an ongoing conflict between the Khmer Rouge and Vietnam.

[40] Some estimates gave the total number of FULRO troops in this period at 7,000, mostly based in Mondulkiri, and supplied with Chinese armaments via the Khmer Rouge, which was by this point fighting its own guerrilla war in western Cambodia.

[45] According to researcher Seb Rumsby, there exist certain but unrecognized imperial relationships between ethnic Kinh colonizers and indigenous minorities, and following that plenty of daily resistance from the Montagnards to systemic state discrimination and repressive assimilation policies.

While marginalization and racial stereotypes about the Montagnards are abundant, few of them can be exactly figured out and acknowledged now, as Kinh chauvinism and fragility have made it difficult for the majority of the country to truly comprehend what the experience of racism of indigenous minorities looks like.