In 1860 von Fransecky was attached to Oldenburg where he commanded an Oldenburgian infantry regiment. In November 1864 he was promoted to major-general and later to lieutenant-general. He was given command of the 7th Division stationed in Magdeburg. In the Austro-Prussian War he distinguished himself at Münchengrätz and Königgrätz, for which he was given the Pour le Mérite. Between 1867 and 1869 von Fransecky served as inspector of the Saxon army.