On 28 November 1787, the government of King Louis XVI of France, represented by Count Montmorin, signed a military aid treaty with Nguyen Anh (the first king of Nguyen Dynasty), represented by Pigneau de Béhaine.
The French promised military assistance to recover the lands occupied by the Tay Son Dynasty, 4 war vessels, 1650 soldiers and equipment. The Vietnamese side gave Hoi An, Con Dao, and commercial rights as concessions to the French. Nguyen Anh also agreed to send military forces, supplie, and arms if France was engaged in a military conflict. Because of the French Revolution in 1789, this treaty was never enforced.