quality:correction
Nguyễn Ánh escapes

In 1775, the 13-year-old Nguyễn Ánh escaped and with the help of the Vietnamese Catholic priest Paul Hồ Văn Nghị soon arrived at the Paris Foreign Missions Society in Hà Tiên. With Tây Son search parties closing in, he kept on moving and eventually met the French missionary Pigneau de Behaine. By retreating to the Thổ Chu Islands in the Gulf of Thailand, both escaped Tây Sơn capture.

Pigneau de Behaine decided to support Ánh, who had declared himself heir to the Nguyễn lordship. A month later the Tây Sơn army under Nguyễn Huệ had returned to Quy Nhơn. Ánh seized the opportunity and quickly raised an army at his new base in Long Xuyên, marched to Gia Định and occupied the city in December 1777. The Tây Sơn returned to Gia Định in February 1778 and recaptured the province. When Ánh approached with his army, the Tây Sơn retreated.

By the summer of 1781, Ánh's forces had grown to 30,000 soldiers, 80 battleships, three large ships and two Portuguese ships procured with the help of de Behaine. Ánh organized an unsuccessful ambush of the Tây Sơn base camps in the Phú Yên province. In March 1782 the Tây Sơn emperor Thái Đức and his brother Nguyễn Huệ sent a naval force to attack Ánh. Ánh's army was defeated and he fled via Ba Giồng to Svay Rieng in Cambodia.