The western frontier of the Third Reich was protected by the Westwall fortifications, better known to the Allies as the Siegfried Line. The Allies began encountering the Siegfried Line in September 1944 after pursuing the retreating Wehrmacht through Belgium and the Netherlands. Fighting along the Westwall lasted for more than six months, with the final major operations in March 1945 in the Saar
The Wehrmacht in the west was in a desperate crisis. Following the Allied breakout from Normandy, the German forces in northern France had become enveloped in a series of encirclements starting with the Roncey pocket, the Falaise pocket, the River Seine, and the Mons pocket in Belgium. These catastrophes destroyed much of the 7th and 15th armies along with parts of the 19th Army. The US Army staged a second amphibious landing on the Mediterranean coast in southern France.
The momentum of the campaign in northwest Europe began to slow abruptly as the Allies outran their supply lines. Initial planning had not anticipated that the Allied armies would advance so rapidly, and logistics were beginning to place a limit on Allied operations. On September 11, 1944, the first day US troops entered Germany, the Allies were along a phase line that the Operation Overlord plans did not expect to reach until D+330 (May 2, 1945) - some 233 days ahead of schedule.
The German situation in the early autumn of 1944 was still desperate, but as the Wehrmacht reached the German frontier, the summer panic subsided and a sober stoicism returned. It was one thing to give up Holland and Belgium, but the western region of Germany was another matter altogether. By the time that the retreating survivors of Army Group B reached the frontier, new defenses had already been stitched together along the Siegfried Line using replacement units, local training units, and an assortment of rear-area troops.
Generalfeldmarschall (GFM) Gerd von Rundstedt returned to command the OB West (Oberbefehlshaber-West, or Supreme Command West), having been relieved of the same post previously over disagreements with Hitler about operations in France. Following Rundstedt's reappointment, Walter Model remained as the Army Group B commander, responsible for the forces in northwestern Germany and Holland. The Aachen corridor was defended by the 7th Army, commanded by Erich Brandenberger.
Omar Bradley's 12th Army Group included two armies, Courtney Hodges' First and George Patton's Third. Much like Bradley, Hodges was a quiet professional, and so very much unlike the flamboyant Patton. However, Hodges did not have Bradley's intellectual talents and had flunked out of the US Military Academy, making his way up the command ladder through the ranks. He was in Bradley's shadow for much of the war, and many senior officers felt he gave too much power to his dynamic chief of staff, Maj Gen William Kean. Hodges was an infantryman with a dependable but stolid operational style.
The collapse of the Wehrmacht after the disasters in Belgium in early September 1944 was partly averted by absorbing territorial and training units once its battered divisions reached Germany. The Wehrmacht consisted of both a Field Army, which controlled tactical combat units, and a separate Replacement Army (Ersatzheer) within Germany itself. In desperation, the untrained units from the reserve training divisions and sometimes even the staffs of the training schools were thrown into combat. Each military district also had several Landesschutzen battalions, local home guard units made up of older men, and usually commanded by World War I veterans.
The unification of command of these disparate units did not take place until early September, with the reconstitution of the 7th Army. Following the encirclement in the Falaise pocket and the deeper envelopment on the Seine, the German 7th Army ceased to exist and its remnants were attached to the 5th Panzer Army. It was reconstructed under Gen Erich Brandenberger and assigned the task of defending the Westwall in the Maastricht-Aachen-Bitburg sector. Recognizing the weakness of the units assigned to the 81st Corps, the 7th Army attempted to reinforce the Aachen sector as soon as resources became available, and three divisions were assigned.
The Westwall program began in 1938, but the role of the Westwall was fundamentally different from the much more elaborate Maginot Line nearby in France. It was intended as a defensive fortified zone facilitating offensive action. The initial construction program ignored the Aachen area, since it faced neutral Belgium. Once the section facing central France was complete, Hitler decided to extend the Westwall along the Belgian frontier due to concerns that the French could deploy their mobile forces through Belgium. By 1944 the line was largely abandoned and the German defenders had to hastily reinforce it.
The US Army by the time of the Siegfried Line campaign had moved beyond its growing pains and had become an experienced and highly capable force. First Army included some of the most experienced US units such as the 1st Infantry Division and 2nd Armored Division, which had served in North Africa, Sicily, and Normandy. Combat leaders were experienced and battle hardened.
Allied planning for the defeat of Germany intended to "rapidly starve Germany of the means to continue the war," with an emphasis on the capture of the two industrial concentrations in western Germany, the Ruhr and the Saar basin. Of the two, the Ruhr industrial region was the more significant, and the loss of the Ruhr combined with the loss of the Low Countries would eliminate 65 percent of German steel production and 56 percent of its coal production. Four traditional invasion routes into Germany were considered: the Flanders plains, the Maubeuge-Liege-Aachen corridor to the north of the Ardennes, the Ardennes-Eifel, and the Metz-Kaiserslautern gap.
The short-term objective in the Wehrmacht was simply to survive after the devastating losses suffered in the summer. This process was greatly aided by two factors: the returning morale of the German troops on reaching German soil, and the halt in the Red Army offensive in Poland. The panic and chaos in the units of Army Group B quickly subsided. Even if the Westwall was more symbolic than real, there was a sense that the frontier could and should be defended.
The central element in determining the shape of German operational planning in the west was Hitler's decision to launch a counteroffensive against the Allies sometime in the late autumn or early winter. The plan was dubbed Wacht am Rhein ("Watch on the Rhine"), a deliberate deception to suggest that the forces being mustered for the Ardennes attack were merely being gathered to conduct the eventual defense of the River Rhine. The plan required that the most capable units, the Panzer Panzergrenadier and best infantry divisions, be withheld from the autumn fighting and built back up to strength in time for the operation.