In 1863 Wittich became Chief of the General Staff of the II Army and in 1864, he was head of the IV Army Corps. As a colonel in this position, he took part in the Austro-Prussian War with great honors and received the order Pour le Mérite for this. On March 22, 1868 he became major general and commander of the 49th Infantry Brigade (1st Grand Ducal Hessian), which he commanded in the Franco-Prussian War in the battles of Battle of Vionville, Battle of Gravelotte and Battle of Noisseville. On September 22, he was appointed lieutenant general, command of the 22nd division. At the head of which he took part in the arduous and long operations on the Loire and against Le Mans from October 1870 to January 1871. In the course of these battles he fought under General von der Tann on October 10 in the Battle of Artenay, on the 11th at Orléans and on the 18th in the assault on Châteaudun. On October 21 he occupied Chartres and then fought under the Grand Duke of Mecklenburg-Schwerin on December 2 at the Battle of Loigny–Poupry ,on 3 and 4 again at Orléans, from 8 to 10 at Battle of Beaugency and contributed significantly to the Victories in the battle of Le Mans (January 10 to 12) and at Alençon (January 15).