General von Stettner came from a well-respected military family. He fought in World War I, serving with the
Bavarian Leib Regiment throughout. He started World War II as commander of a Gebirgsjäger-Regiment and fought in Poland, Norway, Yugoslavia, and the Soviet Union, where his unit advanced into the Caucasus. On 17 December 1942, he replaced
Hubert Lanz as commander of the
1st Mountain Division, when the Division was retreating to the
Kuban Bridgehead, and in April 1943 he was awarded the Knight's Cross of the Iron Cross for his contribution to the defence of the Bridgehead. In April 1943, the 1st Mountain Division was transferred to Yugoslavia for anti-partisan operations. Still under Stettner's command, the division committed several war crimes in Yugoslavia and Greece, including the
Massacres of Kommeno,
Mousiotitsa,
Lyngiades,
Borovë and the
Massacre of the Italian Acqui Division. ==Disappearance and aftermath==