Thiệu Trị
In 1847, French warships under Augustin de Lapierre and Charles Rigault de Genouilly demanded that persecutions cease, and that Da Nang be remitted to them in application of the 1787 Treaty of Versailles. The French sank the Vietnamese fleet in Da Nang in the Bombardment of Đà Nẵng (1847), and negotiation with Emperor Thiệu Trị broke down.