In early 1809, the Austrian Empire prepared a new war against the French Empire. Colonel Roussel d'Hurbal played a conspicuous part in the Austrian victory against Napoleon at Aspern-Essling. During the second day of battle, on 22 May 1809, the colonel received a sabre cut that pierced his helmet, but did not cause a sufficiently serious wound to prevent him from retaining command. One day after the battle, he was promoted to General-Major and was entrusted with the command of a powerful heavy cavalry brigade, around 1,000 sabres strong, composed of the 3rd "Herzog Albert" Cuirassiers and the 2nd "Erzherzog Franz" Cuirassiers. His brigade was heavily engaged against the French and their allies at the great Battle of Wagram on 5 and 6 July 1809, which saw the Austrian army decisively defeated by Napoleon's forces.