Siamese-Vietnamese Wars
The Siamese-Vietnamese Wars were a series of conflicts that arose in the context of political instability in Southeast Asia, particularly in Cambodia, during the late 18th and early 19th centuries. Triggered by a civil war in Cambodia, both Siam (present-day Thailand) and Vietnam intervened on behalf of rival claimants to the Cambodian throne. Initially, Siam emerged as a significant power in the region, successfully restoring the Cambodian king Ang Non with military support despite multiple Vietnamese counterattacks.
However, the balance of power shifted over time, with Vietnam regaining influence in Cambodia following several Siamese invasions. Notably, a Siamese army invaded Cambodia in 1831, leading to further conflicts as both nations vied for dominance over the region. By 1845, after several years of warfare and political maneuvering, a compromise was established where both Siam and Vietnam shared protectorate status over Cambodia, although Siam's influence was greater at that time.
The dynamics of these wars were significantly altered by the arrival of French and British colonial powers in Southeast Asia starting in the 1850s, ultimately leading to the decline of both Siamese and Vietnamese imperial aspirations in the region. Amidst these complex historical interactions, the Siamese-Vietnamese Wars illustrate the intricate political landscape of Southeast Asia during a transformative period.
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Siamese-Vietnamese Wars
At issue: Control of Cambodia
Date: 1769–1845
Location: Cambodia
Combatants: Siamese (Thais) vs. Vietnamese
Principal commanders:Siam, General Phraya Taksin (d. 1782); Vietnam, Nguyen Phuc Anh, later Gia Long (1762–1820)
Principal battles: Kompong Chang
Result: Cambodia becomes a battleground for southeast Asian dominance between Siam and Vietnam
Background
A civil war in Cambodia led to both Vietnamese and Siamese invasions on behalf of rival claimants to the throne. The Siamese claimant won, but Vietnam annexed border territory in the Mekong River region, which continued to be a source of conflict. Siam became weak and divided after the death of King Boromokot, in 1758, leading to a long period of Burmese attacks, mainly under Alaungpaya, and the destruction of the capital of Phra Nakhon Si Ayutthaya, in 1767. Although General Phraya Taksin was unable to keep Burma from overrunning the provinces of the Malay peninsula, he did subdue two rivals to the throne, emerging as the political leader of Siam.
Action
During the 1770’s, Siam emerged as the predominant Southeast Asian power. When Cambodia’s tributary king, Ang Non, was deposed in a Vietnamese-backed coup, a Siamese army under Phraya Taksin invaded Cambodia, occupying Siem Reap and Battambang, in 1770. Vietnamese counterattacks at Trat and Chanthaburi led Taksin to launch a combined land and sea invasion of Cambodia, forcing Vietnam’s puppet ruler to flee and restoring Ang Non to the throne. Although he was briefly deposed again by Vietnamese forces after their victory at Phnom Penh, Ang Non was back on the throne again by 1775, under Siamese suzerainty. Siam also repulsed further Burmese attacks and invaded Laos in 1778, forcing it to recognize Siamese suzerainty.
Weakened by a long civil war, Vietnam was open to attack from Siam, though direct intervention ended with the death of Phraya Taksin. Thereafter, Siam aided Nguyen Phuc Anh, who eventually succeeded to the throne, assuming the imperial title of Gia Long in 1802. Siam then became a major participant in Vietnamese politics.
After a tense period, during which King Ang Chan II of Cambodia paid tribute to both Siam and Vietnam, the king’s brother, Ang Snguon, revolted with the help of a Siamese army. Vietnam sent a formidable army to restore Ang Chan to the throne, Siam withdrew without battle, and Vietnam again became the dominant power in Cambodia. In 1831, a Siamese army under General P’ya Bodin invaded Cambodia, defeating the Vietnamese-backed Khmer (Cambodians) at the Battle of Kompong Chang and forcing King Ang Chan II to flee to Vietnam, in 1832. The Siamese then invaded Vietnam, advancing to Chau-doc and Vinh Long, in southern Vietnam. A general uprising against Siamese control and a 15,000-man Vietnamese army drove the Siamese out of Vietnam, in 1833, and Ang Chan II was restored to the throne, leaving Cambodia once more under Vietnamese control.
By 1841, the Cambodians rebelled against Vietnamese oppression and sought Siamese help in placing the exiled Cambodian prince Ang Duong on the throne. P’ya Bodin led another army which successfully placed Ang Duong on the throne but could not dislodge the Vietnamese from their numerous garrison towns throughout the countryside. After four years of fierce warfare, a compromise was agreed to in 1845, with both occupying powers agreeing to share protector status in Cambodia, though Siamese power was greater.
Aftermath
French and British intervention throughout southeast Asia, beginning in 1850, forced both Vietnam and Siam to abandon imperial pretenses. A limited French protectorate was established in Cambodia in 1863.
Bibliography
Chandler, David P. A History of Cambodia. 2d ed. Boulder, Colo.: Westview Press, 1992.
Chaophraya Thiphakarawong (Kham Bunnag). The Dynastic Chronicles: Bangkok Era, the First Reign. Edited and translated by Thadeus Flood and Chadin Flood. Tokyo: Centre for East Asian Cultural Studies, 1978.
Vella, Walter F. Siam Under Rama III: 1824–1851. Locust Valley, N.Y.: J. J. Augustin, 1957.
Wyatt, David K. “The Subtle Revolution of Rama I.” In Moral Order and the Question of Change: Essays on Southeast Asian Thought, edited by A. B. Woodside and David K. Wyatt. New Haven, Conn.: Yale University Press, 1982.
‗‗‗‗‗‗‗. Thailand: A Short History. New Haven, Conn.: Yale University Press, 1984.