In 1888, a French adventurer convinced Vietnamese tribes to crown him king

Charles-Marie David de Mayrena, self-proclaimed King of Sedang (Wikimedia Commons) | Public domain

In 1888, a French government official named Charles-Marie David de Mayréna was sent into the highlands of what is now Vietnam to negotiate treaties with local tribes. Instead, he convinced the tribes to crown him king. He took the name Marie the First, esta…