Sino-French War of 1884–85

a French war against China for control over all of Vietnam, which was nominally a vassal state of the Manchu dynasty of China.

The French colonialists had seized southern Vietnam in the 1860’s and 1870’s, and in 1883–84 they launched an offensive against the Vietnamese, who were supported by detachments of Black Flag Chinese. (The Black Flags were rebel detachments of Chinese peasants who had fought against the Manchu authorities until 1868, when they had been forced to flee to Vietnamese territory.) The French managed to occupy a number of strategic points in northern Vietnam. In May 1884, Chinese and French representatives signed a convention stipulating that the Manchu authorities would withdraw the troops they had sent into Vietnam in 1882–83 and would recognize any treaties signed between France and Vietnam.

On June 6, 1884, France forced Vietnam to sign a peace treaty establishing a French protectorate over Vietnam. The Manchu government refused to recognize the Franco-Vietnamese treaty. This refusal and the annihilation of a French unit by Chinese and Vietnamese troops in the region of Bac Lieu in June 1884 was the pretext for the French colonialists to unleash the war of 1884–85. On Aug. 23–24, 1884, a French squadron attacked the southern squadron of the Chinese Navy at its anchorage in the Fuchou region, sinking 22 Chinese vessels and destroying the arsenal and the coastal fortifications. French naval forces subsequently made a series of attacks on the coast of China and the island of Taiwan.

In Vietnam, military operations went against the French. In December 1884 regular Manchu troops, together with the Black Flag detachments incorporated in their ranks since the outbreak of war, defeated the French in the Sanxi region; in March 1885, Chinese and Vietnamese troops dealt the French a setback near Lang Son and occupied that city. However, a faction within the Manchu government that favored ending the war and giving concessions to the French gradually won the upper hand. In the spring of 1885 the Manchu government opted for a peaceful settlement and ordered the withdrawal of its forces from Vietnam, including the Black Flag units. On June 9, 1885, the Chinese and French signed the Tientsin Treaty of 1885, by which the Manchu government recognized the French protectorate over Vietnam and granted a number of trading privileges to France in the provinces of Yunnan and Kwangsi, which border Vietnam. As a result of the war, all of Vietnam became a de facto French colonial possession.