Vietnam was a place for many religions such as Confucianism, Buddhism and local practices. The elite in Vietnam were educated in Chinese and Confucianism while the peasantry believed in a variety of syncretic traditions that combined Buddhism and local beliefs.
The French missionaries had introduced Christianity in Vietnam.
The 18th century was marked by significant religious movements against the cultural attack of the French. One such movement was the Scholars Revolt of 1868 and was a protest against French rule and the spread of Christianity.
Hoa Hao was one such movement against the French which started in 1939 and became a rage in the Mekong Delta. The man behind this movement was Huynh Phu So.
Huynh Phu So was sent to a mental asylum insane and later was exiled with his followers to concentration camps. Concentration camps refer to prisons where people were detained without due process of law.
Overall, religious movements had a contradictory relationship with mainstream nationalism. Religious movements were certainly successful in provoking anti-imperialist sentiments.