The research focuses on how the Nguyen dynasty it became the first to have the largest territory in the history of Vietnam in its nearly 60 years of establishing and reigning over the unified country in the first half of the 19th century. It is seen that in terms of organizing the state apparatus, Gia Long and Minh Mang retained the system of agencies of the previous dynasties and continued reforms to ensure socio-political stability in their governance at that time. The study also clarifies the social role of Confucianism in the Nguyen dynasty, i.e. in the first half of the 19th century, which, in our opinion, is theoretically and practically significant, with the hope of further unraveling the role of Confucianism in that period