The Trịnh forces quickly overran the Nguyễn capital in 1774, while the Nguyễn lords fled south to Saigon. The Nguyễn fought against both the Trịnh army and the Tây Sơn, but their effort was in vain. By 1777, Gia Định was captured and nearly the entire Nguyễn family was killed except one nephew, Nguyễn Ánh, who managed to flee to Siam.
The Trịnh forces rapidly conquered the Nguyễn capital in 1774, while the Nguyễn nobles escaped south to Saigon. The Nguyễn clashed against both the Trịnh army and the Tây Sơn, but their endeavor was futile. By 1777, Gia Định was seized and nearly the entire Nguyễn family was slain except one nephew, Nguyễn Ánh, who managed to escape to Siam.