At the end of the 18th century, the Qing Dynasty expanded to invade the outer regions of Mongolia, Xinjiang, Qinghai, and Tibet. After pacifying the North, they are about to invade our country. When Le Chieu Thong went to ask for help, the Qing Dynasty took the opportunity to launch a war to invade our country.

The Qing army divided into four armies to attack our country:

The first army, commanded by Ton Si Nghi, passed through Lang Son and advanced to Thang Long.

The second army, commanded by the prefect Sam Nghi Dong, passed through Cao Bang and advanced

The third army, commanded by Admiral O Dai Kinh, passed through Tuyen Quang and advanced

The fourth army entered through Quang Ninh road.

Materials: Vietnam History Book Volume 01 – p 318 Hanoi Social Sciences Publishing House 1971