Napoleon faced Archduke Charles's Austrian army at the Battle of Eckmühl, on 21–22 April 1809. On 22 April, the second day of the battle, Nansouty was at first sent to the Schierling plain, in support of Bavarian General Deroy, who, after several failed attempts, managed to take the town of Eckmühl from the enemy. Apart from the Schierling plain, the terrain at Eckmühl was very uneven and hilly, with dangerously steep slopes, which made cavalry action here improper. Yet, it was here that one of the most memorable cavalry actions of the entire Napoleonic Wars was to take place. It all began on the slopes next to Eckmühl, where a first brief cavalry engagement occurred, as Bavarian and Württemberger cavalry encountered and charged Austrian cavalry. The Austrians won out and the Bavarians and Württembergers retreated and reformed in the vicinity of the two French heavy cavalry divisions present. These two divisions, the 1st under Nansouty ("1st and 2nd Carabiniers-à-cheval", 2nd, 3rd, 9th and 12th Cuirassiers) and the 2nd under Saint-Sulpice (four regiments strong), were placed next to one another, forming five lines, with their regiments in column, one in front of the other. These men were ordered forward, up the slope and onto the plateau where the light cavalry had been repulsed moments earlier. Arriving on the plateau at a gallop, the cavalry overtook Marshal Lannes's infantry, who admiringly cheered "Vive les cuirassiers" ("Long live the cuirassiers") and applauded as the cavalry galloped past them. With their two frontline regiments now deployed in line and with the German light cavalry protecting their flanks, the two heavy cavalry divisions clashed into whatever Austrian cavalry they could find on the plateau, repulsing them with ease. This was, however, only the prelude of a much larger cavalry combat.