Tonkin Affair

The Tonkin Affair, (French: L'Affaire Tonkin) named after the French colony and protectorate of Tonkin, or Đông Kinh, of March 1885 was a major French political crisis that erupted in the closing weeks of the Sino-French War. It effectively destroyed the political career of the French prime minister, Jules Ferry, and abruptly ended the string of Republican governments inaugurated several years earlier by Leon Gambetta. The suspicion by the French public and political classes that French troops were being sent to their deaths far from home for little measurable gain, both in Tonkin and elsewhere, also discredited French colonial expansion for nearly a decade.

The "Affair" (as most French political scandals are still termed), was triggered on 28 March 1885 by the controversial Retreat from Lang Son. The retreat, which threw away the gains of the February Lang Son Campaign, was ordered by Lieutenant-Colonel Paul Gustave Herbinger, the acting commander of the 2nd Brigade, less than a week after General François de Négrier's defeat at the Battle of Bang Bo (24 March 1885). General Louis Brière de l'Isle, the commander-in-chief of French forces in Tonkin, was in Hanoi at the time, and was planning to shift his headquarters to Hung Hoa, to supervise a planned offensive against the Yunnan Army around Tuyen Quang. Brière de l'Isle concluded that the Red River Delta was in jeopardy and fired off a telegram on the evening of 28 March to the French government, warning that the Tonkin Expeditionary Corps faced disaster unless it was immediately reinforced:

I am grieved to tell you that General de Négrier is seriously wounded and Lang Son has been evacuated.

The news contained in the 'Lang Son telegram', as it was immediately dubbed, ignited a political crisis in Paris:

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