Enghien spent the next winter, as every winter during the war, amid the gaieties of Paris. The summer campaign of 1645 opened with the defeat of Turenne by Franz von Mercy at Mergentheim, but this was retrieved in the victory of Nördlingen, in which Mercy was killed, and Enghien himself received several serious wounds. The capture of Philippsburg was the most important of his other achievements during this campaign. In 1646 Enghien served under Gaston, Duke of Orléans in Flanders, and when, after the capture of Mardyck, Orléans returned to Paris, Enghien, left in command, captured Dunkirk (11 October).