He embraced the ideas of the French Revolution, and soon after its outbreak enlisted in the Parisian National Guard and joined the Cordeliers,[1] eventually becoming a friend of Georges Danton.

Brune was noted as having been particularly incompetent; one anecdote has him attempting to march three divisions down the same road, leading to confusion among the army of Italy.

[4] Following his coronation as Emperor of the French in 1804, Napoleon made Brune a Marshal of the Empire (Maréchal d'Empire)[2] while he was still in Constantinople.

During the campaigns against Austria during the War of the Third Coalition, Marshal Brune commanded the army in Boulogne from 1805 to 1807 overseeing drilling and keeping a watchful eye on the British.

Here he defended Southern France against the forces of the Austrian Empire and Kingdom of Sardinia, with the addition of the British Mediterranean Fleet and local Royalist guerrillas.

[5] He managed to arrive safely with two aides-de-camp in Avignon, but was there shot and killed by an angry Royalist mob after being chased into a hotel, as a victim of the Second White Terror.

[6] An inquiry compelled by his widow later made public that Brune's murder had been covered up by the royal authorities, and revealed that the mob responsible was led by baseless allegations that Brune was the one parading Marie Thérèse Louise of Savoy, Princesse de Lamballe' head on a pike around Paris during the September Massacres.