In 1798 Nordmann was appointed to the rank of Oberstleutnant in the Habsburg service. When the War of the Second Coalition broke out, he fought at the First Battle of Stockach on 25 March 1799 and at Andelfingen in May. On 17 March 1800, he received promotion to Oberst of the "Latour" Dragoon Regiment # 11. In May he led his regiment at the battles of Second Stockach and Messkirch. He performed notable service in action at Neuburg an der Donau on 27 June. After the end of the armistice, he fought at the Battle of Ampfing on 1 December 1800. Two days later, he commanded his cavalrymen at the Battle of Hohenlinden in Paul Esterházy's brigade of Prince Friedrich Karl Wilhelm Hohenlohe-Ingelfingen's division in Ludwig Baillet de Latour-Merlemont's Right Center column. During the retreat after Hohenlinden, the "Latour" Regiment fought at Salzburg on 14 December and Schwanenstadt on the 16th.