Dilger was born in Engen in the Black Forest region of the Grand Duchy of Baden and educated in the Karlsruhe Military Academy.

When news came of the outbreak of the American Civil War, Dilger received a leave of absence and sailed to the United States.

On May 2, 1863, Dilger fought in the rearguard of the retreating Union XI Corps during the disastrous Battle of Chancellorsville, for which he eventually was awarded the nation's highest decoration in 1893.

Dilger also received high praise in the Official Records of the Battle of Gettysburg and for his work in the 1864 Atlanta Campaign during which his battery fired the rounds that killed Lt. General Leonidas Polk.

After the war, Dilger prospered in Ohio and eventually purchased a sprawling horse farm in the Shenandoah Valley near Front Royal, Virginia, where he raised his family.