Following the outbreak of the revolution, Brissot became the editor of Le Patriote Français, a prominent newspaper at the time. Under Brissot, the Girondists supported wars against the neighbouring monarchies and a federalist government in the style of the newly-formed United States. He also rallied the Legislative Assembly to declare war on Austria in 1792.
Initially, the war proved disastrous for France, and the governing Girondists fell from grace. The Jacobins became more powerful, and the National Guard under François Hanriot surrounded the National Convention in May 1793. Armed with cannons, Hanriot demanded that the Girondists were arrested. The deputies of the Convention complied, and Brissot and several Girondists were imprisoned. Brissot was guillotined on 31 October 1793.
Flushed with pride for his role in overthrowing the Girondists, the politician Lemaitre acquired Brissot's head with the help of Captain LeNôtre. The heads of Brissot and Olympe de Gouges were then placed in chests at the Conciergerie. In 1794, the Assassin Arno Dorian retrieved the heads and gave them to Marie Tussaud, a sculptor charged with producing death masks of famous victims of the guillotine.