At the Battle of Wagram on 5–6 July 1809, the 1st Cuirassiers numbered 486 men. At mid-morning a crisis arose as the Austrian III and VI Corps advanced menacingly against Napoleon's left flank. The VI Corps brushed aside an isolated French infantry division on the far left while the III Corps threatened to smash the Franco-Allied left center. To gain time, Napoleon ordered Marshal Jean-Baptiste Bessières to lead the divisions of Nansouty and Antoine-Louis Decrest de Saint-Germain (leading Saint-Sulpice's former division) in charging the Austrians. While the Austrians were occupied in fending off the French heavy cavalry, Napoleon collected a battery of over 100 artillery pieces backed by Jacques MacDonald's corps and the Imperial Guard. At the same time the French emperor ordered Marshal André Masséna to march his corps from the center to the left flank. A little later, Saint-Germain's horsemen were instructed to cover Masséna's maneuver. These measures were successful in halting the Austrian advance, but the heavy cavalry lost 1,200 horses, not counting the human casualties.