The rise of Qui Nhon

In the 1770s, war broke out among the Vietnamese. The immediate cause was an uprising in Binh Dinh Province against the misgovernment of Truong Phuc Loan. People in Binh Dinh had for generations borne the brunt of demands for soldiers, supplies, and transport to sustain Nguyen Phuc policy in the Mekong plain as well as in the mountainous hinterlands. When an ascendant Siam began to challenge the Vietnamese position in Cambodia and the court at Phu Xuan could not rise above a morass of corruption and incompetence, a new political force emerged in Binh Dinh.

In 1767, Burmese invaders seized Ayutthia, the capital of Siam. A provincial Siamese governor named Taksin subsequently expelled the invaders and reigned as king for fourteen years (1768–1782). Taksin’s father, a Teochow Chinese, had made a career as a Siamese tax collector while also being active in the Chinese merchant community of Siam. Taksin had spent part of his youth doing business in Cambodia and reportedly learned to speak both Khmer and Vietnamese. He launched his bid to become king of Siam from Chanthaburi, on the southeastern coast of Siam near the Cambodian border. His familiarity with Cambodia may explain his desire to reduce this Siamese neighbor to vassalage. His means of accomplishing this was to champion the cause of a Khmer prince who came to be known as Chei Chéttha V, the son of Chei Chéttha IV, a former king who had died in 1757.