Antonin Proust was born at Niort, Deux-Sèvres. In 1864 he founded an anti-imperial journal, La Semaine hebdomadaire which appeared in Brussels. He was war correspondent for Le Temps in the early days of the Franco-German War, but after Sedan he returned to Paris, where he became secretary to Gambetta and superintended the refugees in Paris. He entered the Chamber as deputy for his native town in 1876, taking his seat on the left. In Gambetta's cabinet (1881–1882) he was minister of the fine arts, and in the Chamber of Deputies he was regularly commissioned to draw up the budget for the fine arts, after the separate department had ceased to exist. Prosecuted in connection with the Panama scandals, he was acquitted in 1893. From this time he lived in the closest retirement. On 20 March 1905 he shot himself in the head, dying of the wound two days later.