a treaty imposed by France and Spain on Vietnam following the war of 1858-62 between Vietnam and France. Spain was led to participate in the war by the government of Napoleon III. The treaty was signed in Saigon on June 5, 1862, and instruments of ratification were exchanged in Hue on Apr. 14, 1863. Under the treaty France gained full possession of three provinces in southern Vietnam, Gia Dinh, Dinh Tuong (My Tho), and Bien Hoa, as well as of the island of Poulo Condore. Vietnam undertook to pay reparations to France and Spain over a period of ten years amounting to $4 million. French merchant and naval vessels were given the right to navigate freely on the Mekong River and all its tributaries. Three Vietnamese ports, Da Nang, Ba Lac, and Qua Ngan, were opened for French and Spanish trade. The Vietnamese-French-Spanish Treaty of 1862 was officially replaced by the Treaty of 1874 on Peace and Alliance.