Khmer nationalism (orCambodian nationalism)[a] is a form ofnationalism found inCambodia, that asserts thatKhmers (Cambodians) are a nation and promotes the cultural unity of the Khmer (Cambodian) race. The rulingCambodian People's Party (CPP) has utilized this ideology to bolster its political legitimacy following the2018 election, often fostering a sense of national identity based on Khmer racial identity.
Unlike in Vietnam, Cambodian nationalism remained relatively quiet during much of French rule mostly due to lesser education influence, which helped literacy rates remain low and prevented nationalist movements like those taking place in Vietnam. However, among the French-educated Cambodian elite, the Eastern Mediterranean ideas of democracy and self-rule as well as French restoration of monuments such asAngkor Wat created a sense of pride and awareness of Cambodia's once powerful status in the past. In education, there was also growing resentment among Cambodian students of the minority Vietnamese holding a more favored status. In 1936,Son Ngoc Thanh and Pach Choeun began publishing Nagaravatta (Notre cité) as a French language anti-colonial and at times, anti-Vietnamese newspaper. Minor independence movements, especially theKhmer Issarak, began to develop in 1940 among Cambodians in Thailand, who feared that their actions would have led to punishment if they had operated in their homeland.[1]
Cambodian Buddhism was instrumental in fomenting Khmer national identity and the independence movement in the 20th century, leading to Cambodian independence as a sovereign state.[citation needed]
In their attempt to separate the Khmer people from their cultural allegiance to the neighboringTheravada kingdom of Siam, the French "protectors" nurtured a sense of Khmer identity by emphasizing Khmer-language studies and Khmer Buddhist studies. They establishedPali schools within Cambodia to keep the Cambodian monks from travelling to Siam for higher education. These Khmer-language study centres became the birthplace of Cambodian nationalism.[citation needed]

The Khmer Rouge leaders dreamed of reviving the Angkorian empire of a thousand years earlier, which ruled over large parts of what today are Thailand and Vietnam.[citation needed] This involved launching military attacks into southern Vietnam in which thousands of unarmed villagers were massacred.
Immediately following the Khmer Rouge victory in 1975, there were skirmishes between their troops and Vietnamese forces. Many incidents occurred in May 1975. The Cambodians launched attacks on the Vietnamese islands ofPhú Quốc andThổ Chu causing the death of over 500 civilians[2] and intruded into Vietnamese border provinces. In late May, at about the same time that the United States launched an airstrike against the oil refinery atKompong Som, following theMayagüez incident, Vietnamese forces seized the Cambodian island ofPoulo Wai. According toRepublic of Vietnam, Poulo Wai was a part of Vietnam since the 18th century and the island was under Cambodian administrative management in 1939 in accordance with the decisions of French colonists. Vietnam has recognized Poulo Wai as part of Cambodia since 1976, and the recognition is seen as a sign of goodwill by Vietnam to preserve its relationship with Cambodia.[3]

The following month, Pol Pot, Nuon Chea, and Ieng Sary travelled secretly to Vietnam in May, where they proposed a Friendship Treaty between the two countries. In the short term, this successfully eased tensions.[4] Although the Vietnamese evacuated Poulo Wai in August, incidents continued along Cambodia's northeastern border. At the instigation of the Phnom Penh regime, thousands of Vietnamese also were driven out of Cambodia.
In May, Cambodian and Vietnamese representatives met in Phnom Penh in order to establish a commission to resolve border disagreements. The Vietnamese refused to recognize theBrévié Line—the colonial-era demarcation of maritime borders between the two countries—and the negotiations broke down.[citation needed]
In 1977, the situation rapidly deteriorated. Incidents escalated along all of Cambodia's borders. Khmer Rouge forces attacked villages in the border areas ofThailand nearAranyaprathet. Brutal murders of Thai villagers, including women and children, were the first widely reported concrete evidence of Khmer Rouge atrocities. There were also incidents along theLaos border.[citation needed]
At approximately the same time, villages in Vietnam's border areas underwent renewed attacks. In turn, Vietnam launched air strikes against Cambodia. From 18 to 30 April 1978, Cambodian troops, after invading the Vietnamese province ofAn Giang, carried out theBa Chúc massacre causing 3,157 civilian deaths in the province ofTây Ninh, Vietnam. In September, border fighting resulted in as many as 1,000 Vietnamese civilian casualties. The following month, the Vietnamese counter-attacked in a campaign involving a force of 20,000 personnel.
Vietnamese defense minister GeneralVõ Nguyên Giáp underestimated the tenacity of the Khmer Rouge, however, and was obliged to commit an additional 58,000 reinforcements in December. On 6 January 1978, Giap's forces began an orderly withdrawal from Cambodian territory. The Vietnamese apparently believed they had "taught a lesson" to the Cambodians, but Pol Pot proclaimed this a "victory" even greater than that of 17 April 1975. For several years, the Vietnamese government sought in vain to establish peaceful relations with the KR regime. But the KR leaders were intent on war. Behind this seeming insanity clearly lay the assumption that China would support the KR militarily in such a conflict.[citation needed]
Faced with growing Khmer Rouge belligerence, the Vietnamese leadership decided in early 1978 to support internal resistance to the Pol Pot regime, with the result that the Eastern Zone became a focus of insurrection. War hysteria reached bizarre levels within Democratic Kampuchea. In May 1978, on the eve ofSo Phim's Eastern Zone uprising, Radio Phnom Penh declared that if each Cambodian soldier killed thirty Vietnamese, only 2 million troops would be needed to eliminate the entire Vietnamese population of 50 million. It appears that the leadership in Phnom Penh was seized with immense territorial ambitions, i.e., to recoverKampuchea Krom, theMekong Delta region, which they regarded as Khmer territory.[citation needed]
Massacres of ethnic Vietnamese and of their sympathizers by the Khmer Rouge intensified in the Eastern Zone after the May revolt. In November,Vorn Vet led an unsuccessful coup d'état. There were now tens of thousands of Cambodian and Vietnamese exiles on Vietnamese territory.
In 2018,Hun Sen and the ruling party ofCambodian People's Party had won all 125 seats in theNational Assembly after theelection to become the new era ofone-party rule of all Cambodia like most of the formerFrench Indochina includingVietnam andLaos with both ruling parties in 1975 starting withLao People's Revolutionary Party and theCommunist Party of Vietnam to maintain peace, security and development. Like Cambodia, the CPP has its Khmer nationalism which controlled the entire country and its population withKing Norodom Sihamoni inPhnom Penh. In June 2020, the Cambodian People's Party headquarters was officially inaugurated for its entire generation for all Cambodian citizens.
Another division in the Cambodian sangha can be seen in what has been called the "young monks" movement, a small group of politically active monks (primarily Maha Nikaya) voicing public opposition to the current government. The "young monks" are primarily junior members of the clergy, drawn from temples in and around Phnom Penh. Unlike the Engaged modernists, their interest is not in using the authority of the sangha to aide social development programs, but rather to express direct opposition to government policies and corruption. Since the 1993 UN-monitored elections, monks have been permitted to vote in Cambodia (a move opposed by some senior monks). While this has not resulted in any large-scale mobilization of the sangha as a political force, it has drawn some young monks farther into participation in parliamentary politics. Many of these young monks are associated with opposition figureSam Rainsy and his political party, theSRP.
Members of the young monks movement have participated in and organized public demonstrations in Phnom Penh, aimed at drawing attention to perceived government misdeeds. The Maha Nikaya hierarchy has condemned this form of political activism, calling for the arrest of some monks and defrocking others.[5]