Battle of Ulm

The Battle of Ulm on 16–19 October 1805 was a series of skirmishes, at the end of the Ulm Campaign, which allowed Napoleon I to trap an entire Austrian army under the command of Karl Freiherr Mack von Leiberich with minimal losses and to force its surrender near Ulm in the Electorate of Bavaria.

In 1805, the United Kingdom, the Austrian Empire, Sweden, and the Russian Empire formed the Third Coalition to overthrow the French Empire. When Bavaria sided with Napoleon, the Austrians, 72,000 strong under Mack, prematurely invaded while the Russians were still marching through Poland. The Austrians expected the main battles of the war to take place in northern Italy, not Germany, and intended only to protect the Alps from French forces.

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