Generals of the Ardennes: American Leadership in the Battle of the Bulge by Video available at http://youtu.be/8a8fqGpHgsk
The Germans achieved total surprise on the morning of 16 December 1944, due to a combination of Allied overconfidence, preoccupation with Allied offensive plans, and poor aerial reconnaissance. American forces bore the brunt of the attack and incurred their highest casualties of any operation during the war. The battle also severely depleted Germany's armored forces, and they were largely unable to replace them. German personnel and, later, Luftwaffe aircraft (in the concluding stages of the engagement) also sustained heavy losses. The Germans had attacked a weakly defended section of the Allied line, taking advantage of heavily overcast weather conditions that grounded the Allies' overwhelmingly superior air forces. Fierce resistance on the northern shoulder of the offensive, around Elsenborn Ridge, and in the south, around Bastogne, blocked German access to key roads to the northwest and west that they counted on for success. Columns of armor and infantry that were supposed to advance along parallel routes found themselves on the same roads. This, and terrain that favored the defenders, threw the German advance behind schedule and allowed the Allies to reinforce the thinly placed troops. The furthest west the offensive reached was the village of Foy-Nôtre-Dame, south east of Dinant, being stopped by the British 21st Army Group on 24 December 1944. Improved weather conditions permitted air attacks on German forces and supply lines, which sealed the failure of the offensive. In the wake of the defeat, many experienced German units were left severely depleted of men and equipment, as survivors retreated to the defenses of the Siegfried Line.
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