The invasion of Normandy on the 6th of June 1944, better known as D-Day, proved that the German Atlantikwall (defence line along the West European coastline) wasn't invincible as Hitler had claimed. The German army suffered severe losses after the Allied breakthrough and fell apart almost completely. Oberbefehlshaber West (OB West, Commander-in-Chief West) Gerd von Rundstedt could give no advice to Berlin other than 'surrender'. But Hitler had no intention of giving up. Hitler’s reaction to Von Rundstedt's attitude was to relieve him. He made Field Marshal Gunther von Kluge the new OB West. Surrender, and even withdrawal, were out of the question. Von Kluge's task was to stop the Allied advance and launch a counter-attack. Von Kluge was to last 44 days. He was ordered to report to the Führer's headquarters at once. He was one of many people suspected in connection with the July 20th assassination attempt on Hitler. On the night of August 18th on his way to Berlin Von Kluge committed suicide.

Again, another new commander (OB West) was appointed. This time it was Field Marshal Walter Model. Model had the same orders as Von Kluge. In September 1944. he set up the German front line defence south of the Netherlands' main rivers. To the west was Von Zangen's 15th Army. To the east was Student's 1st Parachute Army, and in the south at the Siegfried line was Brandenberger’s 7th Army. Still, there were too few men to stand any chance against the Allies’ superiority. Several times Model asked Berlin to send reinforcements. But Germany didn't have any soldiers available. Every soldier on the East front was indispensable, so they conscripted young and old men, even boys. They were all sent to the Netherlands with police, supply corps men, recovering soldiers and others to prevent the Allied advance at all costs. Now Model’s line stretched from Antwerp (southwest Holland) to Maastricht (south Holland). He ordered the 15th Army to prepare for an assault on Antwerp. Perhaps there would be a chance to isolate the British troops. Model also ordered the 2nd SS Panzer Corps to retreat towards Arnhem. He brought this corps to Arnhem to rest and refit. This decision by Model is one of the reasons, if not the reason, why Operation Market Garden failed.

Still Hitler wasn't satisfied. He believed that Model wasn't capable of restoring the German defence after all. And so, after 18 days, Model was no longer OB West. Three months after his dismissal, Von Rundstedt was again appointed OB West. Hitler ordered him to keep the Westwall (known as the Siegfried line) in readiness. The Siegfried line was a strong defence line, protecting the German industrial areas and was now prepared for an Allied offensive. Von Rundstedt reasoned that Montgomery's advance had come to a halt. The hold-up of the British army wasn't just a short break. Von Rundstedt had followed Montgomery's actions during the war and knew that Montgomery would not attack before everything was arranged in great detail. With this assumption, he saw a chance to save Von Zangen's 15th Army and prevent the Allies from using the port of Antwerp. He cancelled the assault ordered by Model. Instead of an attack, he ordered the 15th Army to retreat to the west, with the exception of some units who had to defend the Canal ports. The British made a big mistake by not stopping this retreat. Now Von Rundstedt had 60,000 more men at his disposal.