Third Coalition

The War of the Third Coalition was a military conflict in 1805 between an alliance of primarily Austria, Portugal, Russia, and Great Britain against France and its client states under Napoleon I. Major engagements between France, Austria, and Russia, the main participants on land, unfolded over much of Central Europe from August to December. Britain, fearing an impending French invasion, dealt a crushing blow to a combined Franco-Spanish fleet at Trafalgar in October and secured mastery of the seas. The war, however, was decided on the continent, and the major land operations that sealed the swift French victory involved the Ulm Campaign, a large wheeling manoeuvre by the Grand Army lasting from late August to mid-October that captured an entire Austrian army, and the Battle of Austerlitz in early December, which led to a decisive French triumph over a combined Russo-Austrian force under Tsar Alexander I.
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