Officially termed Unternehmen Wacht am Rhein, the Ardennes Offensive or Battle of the Bulge, was the last major German campaign on the Western Front during WW2.
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By this stage in late 1944, the Allies had secured a front line from Netherlands to Switzerland and controlled the key port of Antwerp.
The offensive intended to attack in order to split the Allied Armies & take control of Antwerp.
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Using little radio contact & moving troops & armour by night, the Germans launched their initial assault at 05.30 on 16 Dec, 1944, with a 90 minute artillery barrage across a 60 -80 mile front, from Aachen to Bastogne.
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The attack involved over 200,000 men, 1,400 tanks, tank destroyers, and assault guns, and 2,600 artillery pieces. It involved over 20 divisions of the Wehrmacht, Panzer, and SS Armies.
The American troops were approx. 50,000 men and 240 tanks.
(Numbers vary with sources used)
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The Allies were taken by surprise & the size of the attack meant in most areas the Americans were outnumbered at least 2:1, in others 5:1. The heavily overcast weather meant the Allies' superior air support was grounded.
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However, the terrain was an advantage to the Allies whose fierce resistance in the Northern and Southern shoulders of the offensive blocked key roads to the Germans, forcing them to advance in a much smaller area (hence the bulge shape on the maps)
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For example, the U.S 110th Infantry Regt, 28th Infantry Division, suffered a casualty rate of 90%, with just 500 men left from a 5,000 force after holding back the Germans as long as they could. The Allied troops held out in most areas long enough for reinforcements to arrive.
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These reinforcements included the 101st Airborne Division who would become besieged in the area and become known as the Battered Bastards of Bastogne
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