In 1801, he was appointed Colonel-Proprietor (Inhaber) of 7th Dragoon Regiment. Prior to the Capitulation of Ulm, he, Karl Philipp, Prince of Schwarzenberg, and Archduke Ferdinand d'Este broke out of the French cordon surrounding the city and escaped to Bohemia, hotly pursued by the French cavalry. On 5 November, he commanded an Austrian cavalry column at the Battle of Dürenstein and a few weeks later, he commanded the Austrian cavalry at the Allied defeat at the Battle of Austerlitz.