Still a general of brigade, Marulaz found himself leading Marshal André Masséna's IV Corps cavalry division at the outset of the War of the Fifth Coalition. His 2,765-man command included the 3rd, 14th, 19th, and 23rd Chasseurs à cheval Regiments, in addition to the Baden Light Dragoon and Hesse-Darmstadt Chevauléger Regiments. On the morning of 21 April 1809, the 23rd Chasseurs seized the bridge over the Isar River at Moosburg in a brilliant coup. Marulaz's cavalry quickly crossed to the east bank and turned northeast toward Landshut where Johann von Hiller's Austrians were making a stand. That day, Napoleon defeated Hiller in the Battle of Landshut. The emperor hoped to catch the Austrians in a pincer attack between his forces and Masséna's.