In 1808, he and his wife joined the Roman Catholic Church in the Cologne Cathedral. From this time on, he became more and more opposed to the principles of political and religious liberalism. He went to Vienna and in 1809 was appointed imperial court secretary at the military headquarters, editing the army newspaper and issuing fiery proclamations against Napoleon. He accompanied archduke Charles, Duke of Teschen to war and was stationed in Pest during the War of the Fifth Coalition. Here he studied the Hungarian language. Meanwhile he had published his collected "Geschichte" (Histories) (1809) and two series of lectures, "Über die neuere Geschichte" (On Recent History) (1811) and "Geschichte der alten und neuen Literatur" (On Old and New Literature) (1815). In 1814 he was knighted in the Supreme Order of Christ.