자롱
Mạng's father was Emperor Gia Long, who had united Vietnam under its current state. Gia Long had reunited the nation under the newly formed Nguyễn Dynasty with the help of French volunteers recruited by the Jesuit missionary Pigneau de Behaine after more than 200 years of north-south division and multiple wars between the Nguyễn lords in the south and the Trịnh lords in the north.