Respuesta :

Under the Ly Dynasty was when Buddhism become the state religion.

Buddhism became the state religion of Vietnam during Ly dynasty. The Ly emperors established a Buddhist tradition close to that of the other Buddhist kingdoms of East Asia. Buddhism became the official religion, with the emperors and the nobility promoting the construction of pagodas, pilgrimages and taking part in the cult. The Buddhist monks became a privileged class, exempt from taxes and military service.