A friend of Prince William, much of Auerswald's youth was spent in Königsberg. After the completion of his education he entered the 1. Leibhusarenregiment of the Prussian Army. In 1812 as part of Napoleon's invasion of Russia, Auerswald participated in campaigns in Livonia and Courland under the command of Yorck. He also served from 1813–15 during the wars against Napoleon. Auerswald remained in the military until 1821, when he was discharged as a cavalry captain.