Werneck served in Archduke Charles, Duke of Teschen's brilliant Rhine Campaign of 1796. At the Battle of Würzburg on 3 September, he led a division of 12 grenadier battalions in Wilhelm von Wartensleben's Reserve. His brigade commanders were Johann Kollowrat, Joseph von Schellenberg, and Ludwig von Vogelsang. On 18 September he was awarded the Commander's Cross of the Military Order of Maria Theresa. When Charles took troops to join Maximilian Anton Karl, Count Baillet de Latour, Werneck was left in command of the independent "Army of the Lower Rhine" beginning in September. His position remained unmolested by the French during the winter. On 18 April, Lazare Hoche and 38,000 French troops from the "Army of Sambre-et-Meuse" caught Werneck's 21,000 Austrians by surprise in the Battle of Neuwied. After heavy fighting, his soldiers were driven from the field with losses of 1,000 killed and wounded, plus 3,000 captured. In addition, 24 artillery pieces, 60 wagons, and five colors became trophies of the French. Total French losses were 2,000. On 17 April, when Jean Etienne Championnet's division threatened Werneck's right wing, the Austrian general weakened his left under Pál Kray in order to bolster his right. When the divisions of Paul Grenier and François Joseph Lefebvre began crossing the Rhine at 3:00 AM, Werneck hurriedly ordered Kray's troops back to defend his left. Lefebvre defeated the Austrian left flank, while Grenier broke through Kray's line of redoubts at Heddersdorf after repeated assaults. Hoche's offensive forced the Austrians into a deep withdrawal which ended only with news of the Treaty of Leoben. After the defeat, Werneck was placed in retirement on half-pay.