Duhesme studied law and in 1792 was made colonel of a free corps by Charles-François Dumouriez, which he raised by his own means. As commander at Roermond, he held the post of Herstal, an important passage to the Netherlands, and burned the bridge of Leau after the defeat at Neerwinden on 18 March 1793. He then crossed the Schelde and at the Battle of Villeneuve rallied the fleeing infantry (6 July), for which action he was made brigadier general.