Anxious, the Governor-General of French Indochina agreed to a proposal from Mayréna to lead an expedition into the interior in order to negotiate treaties with the local tribespeople.

Mayréna, his supporters and some tribespeople claimed that the tribes were not vassals of the Annamese (Vietnamese) emperor and therefore could form their own kingdom.

[citation needed] He designed a national flag [2] and an honorary insignia—the Order of Marie the First—which he had cast by goldsmiths in Hong Kong.

In 1889 a Belgian financier named Somsy offered arms and money to Mayréna in exchange for mineral rights.

[3] There, on 11 November 1890, Marie I died under mysterious circumstances (various reports claiming by poisoning, snakebite or as the result of a duel) on Tioman Island.