After participating in the Siege of Landau, Delmas was arrested by a representative of the people, yet was released shortly after.

Joining Desaix's corps of the center, he saw much action in the following months, serving at the crossing of the Rhine, Rastadt, and Neresheim.

In April of that year Delmas singled out by General Napoleon Bonaparte and rebuked for beating his troops with his cane.

Delmas fought at the Battles of Engen and Messkirch with this division until replaced by General Grandjean.

Transferred back to Italy, he served under General Brune, distinguishing himself at the Battle of Pozzolo, seizing the redoubts at Salionze, and assisting in the attack on Verona.

In May 1802 he was exiled from Paris, ordered to stay at least 30 miles from the city for his opinions on the Concordat with the Pope.

[2] After the Russian campaign of 1812, there was a need for experienced officers and Delmas requested and was returned to active duty.