After the start of World War II, the 1st SS Totenkopfstandarte
Oberbayern would become the SS-Totenkopf-Infanterie-Regiment 1 of the
SS Division Totenkopf on 16 October 1939 and was later renamed the SS Panzer Grenadier Regiment 5 "Thule" in 1942. During the
Battle of France, Simon led his regiment in the capture of Pixie,
Lyon,
Orléans,
Tours and
Bordeaux and then advanced to the border with Spain. In July 1941, Simon took part in the invasion of Soviet Union,
Operation Barbarossa, as part of
Army Group North, taking
Kraslava and breaking through the
Stalin Line, where Simon was wounded. For the fighting in the Battles of the
Demyansk Pocket, Simon was awarded the Knight's Cross and promoted to
SS-Oberführer (Senior Colonel). In December 1942 Simon was promoted again to
SS-Brigadeführer (Brigadier General), prior to being given command of the
SS Division Reichsführer-SS. The SS Division Reichsführer-SS was to be formed in Hungary from Simon's old regiment and the
Sturmbrigade Reichsführer SS. In 1944, the division was moved to Italy, and fought, never complete, at Anzio and later in the
Arno sector, where it gained a reputation for stability although it suffered heavy losses during the battles in the
Apennines. The division also fought against
partisans behind the lines, perpetrating several major atrocities against civilians (
Sant'Anna di Stazzema massacre and
Marzabotto massacre), for which Simon was awarded the Oakleaves for the Knight's Cross and the
German Cross in Gold, in October 1944. On 24 October with effect from 1 November 1944, Simon was appointed commanding general of the
XIII SS Corps. The XIII SS Corps deployed to the
Lorraine region against the
United States Army, and from December 1944 defended the
Siegfried Line. The XIII SS Army Corps retreated into the
Saarland and the
Palatinate where it started to destroy the
Rhine bridges. In April 1945, between
Main and
Jagst, it came up against the
4th US Armored Division and took part in heavy fighting around the
Tauber – Colombia line and around
Würzburg and
Nuremberg. The Corps then fought a withdrawal to the
Danube and around
Munich. On the orders of Simon the bridges over the
Isar approaching Austria were not blown up, as he believed there was no need as the end of the war was near. ==Killings in Brettheim==