When Emperor Napoleon I of France's Grande Armée moved against Habsburg Austria during the War of the Third Coalition, Malher commanded the 3rd Division in Marshal Michel Ney's VI Corps.

These troops collided with a force of Tyrolean jagers under Konstantin Ghilian Karl d'Aspré to start the Battle of Günzburg.

Malher tried to rebuild the two bridges at Günzburg but was forced to give up under the intense fire of 20 cannons and the Archduke Charles Infantry Regiment # 3.

[5] Later that day, the Austrian commander Karl Mack von Lieberich ordered the bridge on the eastern outskirts of the town to be reconstructed by Ignaz Gyulai.

Malher moved the rest of his division to support the success and the French troops held the bridge against Austrian counterattacks.

[9] After the successful conclusion of the Ulm Campaign, Napoleon sent the divisions of Malher and Louis Henri Loison of Ney's corps to the County of Tyrol.

It had been allowed to cross the Kingdom of Spain by agreement and Spanish forces occupied parts of Portugal.

On the pretext of supporting the occupation force in Portugal, 75,000 French troops crossed into Spain in early 1808 and took over key strategic locations.