He was also a member of the Council of Five Hundred (the lower house of the legislative branch of the French government under The Directory), and a teacher at the military school of Rebais, Champagne.

[1] On his mother's side, he was the grandson of the French writer Pierre Chompré (1698 – 1760); his father, Jean-Claude Defrance, was the medical doctor at the Royal Military School of Rebais, in Champagne.

[3] As Chef-de-Brigade, the equivalent of colonel in France's revolutionary-era field army, Defrance went to Italy and participated in the actions leading up to the Battle of Marengo.

[2] In 1803, with Napoleon's military reorganisation, the title Chef-de-Brigade reverted to colonel; Defrance retained his command of the 12th Regiment of Chasseurs-a-Cheval.

On 1 February 1805, he accepted a promotion to brigadier general and commanded a brigade in the Danube campaign against Austria and Russia at the battles of Ulm and Austerlitz.

There, and at the Battle of Friedland on 14 June 1807, he commanded a carabinier brigade—the first and second regiments—in Étienne Marie Antoine Champion de Nansouty's First Division.

[2] He also commanded the 4th Heavy Cavalry Division at the Battle of Leipzig in October 1813, and one of his brigades remained at Lindenau to cover a possible retreat.

[8] In January 1814, for the last few months of Napoleon's rule, Defrance commanded four regiments of Imperial Guard and fought in the action of 11 February at Montmirail, during the Six Days' Campaign.

During the Hundred Days, Napoleon's brief return to France, Jean-Marie Defrance commanded the cavalry element of the Army of the West.

Under overall command of Jean Maximilien Lamarque, one of Napoleon's fiercest supporters, it was formed to suppress potential Royalist insurrection in the Vendée region of France.