After Mack's Austrian army invaded Bavaria, it found itself the target of a powerful offensive by the army of Emperor Napoleon I of France. When Napoleon's corps threatened to envelop Mack's army, the Austrian general unwisely held his ground near the city of Ulm. As the French armies blocked the Austrian retreat routes to the east, Mack attempted to move his army to the south bank of the Danube. After receiving orders to seize the Danube bridges, Marshal Michel Ney sent Malher to capture the crossing at Günzburg. Malher's main attack on two bridges failed in the face of a vigorous Austrian defense. However, a late-arriving French unit captured the eastern bridge that had just been rebuilt by the Austrians and was able to hold on to it until evening. Discouraged by the encounter, Mack orde