Page "History of Vietnam" Paragraph 39

The Tây Sơn army commanded by Nguyễn Huệ marched north in 1786 to fight the Trịnh Lord, Trịnh Khải.

The Trịnh army failed and Trịnh Khải committed suicide.

The Tây Sơn army captured the capital in less than two months.

The last Lê emperor, Lê Chiêu Thống, fled to Qing-controlled China and petitioned the Manchu-Qing Emperor for help.

The Qing emperor Qianlong supplied Lê Chiêu Thống with a massive army of around 200, 000 troops to regain his throne from the usurper.

Nguyễn Huệ proclaimed himself Emperor Quang Trung and defeated the Qing troops with 100, 000 men in a surprise 7 day campaign during the lunar new year ( Tết ).

During his reign, Quang Trung envisioned many reforms but died by unknown reason on the way march south in 1792, at the age of 40.

During the reign of Emperor Quang Trung, Đại Việt was in fact divided into three political entities.

The Tây Sơn leader, Nguyễn Nhạc, ruled the centre of the country from his capital Qui Nhơn.

Emperor Quang Trung ruled the north from the capital Phú Xuân Huế.

In the South, Nguyễn Ánh, assisted by many talented recruits from the South, captured Gia Định ( present day Saigon ) in 1788 and established a strong base for his force.