Minh Mạng outlaws the teaching of Christianity in Vietnam in February 1825, banning missionaries from entering Vietnam.

French vessels entering Vietnamese harbors are ordered to be searched with extra care.

All entries are to be watched.

Minh Mạng had continued and intensified his father's isolationist and conservative Confucian policies.

His father had rebuffed a British delegation in 1804 proposing that Vietnam be opened to trade.

The delegation's gifts are not accepted and turned away.

Vietnam is under no threat of colonization, since most of Europe is engaged in the Napoleonic Wars.

Nevertheless, Napoleon had seen Vietnam as a strategically important objective in the colonial power struggle in Asia, as he felt that it would make an ideal base from which to contest the British East India Company's control of the Indian subcontinent.

With the restoration of the monarchy and the final departure of Napoleon in 1815, the military scene in Europe quieted and French interest in Vietnam was revived.

Jean-Baptiste Chaigneau, one of the volunteers of Pigneau de Behaine who had helped Gia Long in his quest for power, had become a mandarin and continued to serve Minh Mạng, upon whose ascension, Chaigneau and his colleagues were treated more distantly.

He eventually left in November 1824.

In 1825, he is appointed as French consul to Vietnam after returning to his homeland to visit his family after more than a quarter of a century in Asia.

Upon his return, Minh Mạng receives him coldly.

The policy of isolationism will soon see Vietnam fall further behind and become more vulnerable as political stability returns to continental Europe, allowing her colonial powers a free hand to once again direct their attention towards further conquests.