The Paper Bridge, fought on 19 May 1883, was one of the numerous clashes during the Tonkin Campaign (1883–86) between the French and the Black Flags. A small French force under the command of capitaine de vaisseau Henri Rivière attacked a strong Black Flag defensive position near the village of Cau Giay a few miles to the west of Hanoi, known to the French as Paper Bridge. After initial successes, the French were eventually enveloped on both wings, and were only with difficulty able to regroup and fall back to Hanoi. Rivière and several other senior officers were killed in the action.