1944 had been nearly catastrophic for Nazi Germany. By December, four million German soldiers had been killed during the five-year conflict, and Axis armies had been driven out of most of their conquered territories in the East and West. Adolf Hitler, however, refused to concede defeat to those he deemed his lessors. He was particularly contemptuous of American soldiers, who he considered soft, attributing their success solely to the glut of US industrial production. The winter counteroffensive he concocted in secret was designed to exploit such weakness and bring the fighting in the West to an end.

The operation was called “Wacht um Rhein” (Watch on the Rhine) and included some thirty divisions Hitler had secretly amassed. Many were among the best remaining in the Wehrmacht (regular army) and Waffen-SS, while others were formed by loosening age requirements for new inductees, bringing grandfathers and young teens into the ranks. Hitler’s plan was to attack along a 60-mile front in the rustic Ardennes region of southern Belgium, just as his forces had in 1940. It was a quiet sector guarded by only five American divisions, and to Hitler’s great fortune, three of those were new to the theater and lacked combat experience, while the other two were deeply fatigued and severely understrength after fierce autumn fighting.

The Germans intended to attack in poor weather conditions, nullifying the Allies’ greatest advantage – their air power. After overwhelming the American frontline defenses, Hitler’s armored spearheads would race toward the Meuse River and on to Antwerp, driving a wedge between Allied armies in the north and south. Seizing the Belgian port would be crippling to the Allies, lengthening a war Hitler believed most Americans and British were eager to end. He also believed—quite mistakenly—American and British leaders would readily negotiate a settlement rather than continue to insist on unconditional surrender.

The operation began on December 16. Shrouded in thick fog and under overcast skies, the German armor easily battled past the surprised Americans on the first day, punching a hole and creating a bulge in the lines forty miles wide and sixty miles deep. There were early signs of trouble, though, as US forces had already begun regrouping, stiffening their defenses and moving fresh divisions into the Ardennes. German tanks were also running low on fuel, having few reserves and failing to capture Allied supply depots.

A pivotal battle soon unfolded around Bastogne, a small town that sat astride a critical juncture of paved roads the German armor depended on. After the town had been barricaded by the US 101^st Airborne Division and part of the 10^th Armored Division, it was quickly surrounded by a much larger German force and besieged for days. Amid freezing temperatures, the American paratroopers and tankers held their ground despite lacking cold-weather gear and having little food and ammunition. Days later, clearing skies and the arrival of lead elements of General George Patton’s US Third Army ended the siege. US air power returned, and American reinforcements poured into the Ardennes, thwarting further German advances. Fighting would continue throughout a snowy January, but the Germans were ultimately pushed back to their starting positions, ending the Battle of the Bulge.

It was another stinging defeat for the Germans, with the loss of more than 100,000 soldiers. The Americans suffered 80,000 killed and wounded, but with significant resources still to draw on, they wasted little time resuming their drive to the German border.