After Hoàng Đình Bảo's death, his subordinate in Nghệ An province Nguyễn Hữu Chỉnh defected to Tây Sơn. He was welcomed by the king of Tây Sơn and became a commander in their army. In summer 1786, Nguyễn Nhạc, who wanted to reclaim the land of the Nguyễn lords taken by the Trịnh in 1775, ordered his brother Nguyễn Huệ and Nguyễn Hữu Chỉnh to attack Trịnh lords, but warned them not to advance further north. After taking Phú Xuân, Nguyễn Hữu Chỉnh convinced Nguyễn Huệ to overthrow Trịnh lords under the banner "Destroy the Trịnh and Aid the Lê (, ) that would help them gain support from northern people. Trịnh army and the Three Prefectures Army were quickly defeated. Trịnh Tông committed suicide. Emperor Cảnh Hưng died of old age shortly after and passed the throne to Lê Duy Kì (emperor Chiêu Thống).