He was noted for his friendship with Napoleon Bonaparte, who appointed him as the first Grand marshal of the palace, the head of the Emperor's military household.

In July 1792, he left the artillery school to become an emigré soldier in the counter-revolutionary Army of Condé, at the start of the Revolutionary Wars.

[2] Duroc joined the French Revolutionary Army on 1 June 1793, being assigned lieutenant en seconde of the 4th Foot Artillery Regiment,[2] and advanced steadily in the service.

As Grand Marshal of the Palace, Duroc was responsible for the measures taken to secure Napoleon's personal safety, whether in France or on his campaigns, and he directed the minutest details of the imperial household.

After the Battle of Austerlitz, where he commanded the grenadiers in the absence of General Oudinot, he was employed in a series of important negotiations with Frederick William III of Prussia, with the elector of Saxony (December 1806), in the incorporation of certain states in the Confederation of the Rhine, and in the conclusion of the armistice of Znaim (July 1809).

At the Battle of Reichenbach on 22 May 1813, a cannonball ricocheted off a tree-trunk, hit Duroc in the stomach, tore open his belly and spilled out his intestines in a gory mess over uniform, saddle and horse,[3] which Napoleon witnessed.