 During the French Revolutionary Wars Donzelot served in the campaigns of the "Army of the Rhine" under the command of Pichegru and Moreau.In 1798 Donzelot served in the French campaign in Egypt and Syria, distinguishing himself at Cairo and Battle of Heliopolis and in 1799 he was made a temporary general de brigade, the rank made permanent in 1801.After his return to France he served on the staff of the minister of war, Berthier.