Factual error: In the opening scene, the German soldiers are searching the Americans. They remove a package of Lucky Strike cigarettes from one of the Americans. This package has the red circle against the green background. Green ink was stopped in 1942 because it uses chromium for green pigment which was necessary for war production of steel. Slogan "Lucky Strike Greens Has Gone to War" was a big advertisement in 1942 with introduction of white background on package.
Factual error: The beginning of this movie is based on an actual historical occurrence. On December 17th 1944, SS troops of the 1st SS Panzer Division did kill a substantial number of US POWs in a field a few miles away from Malmedy, Belgium. The G.I POWs and main characters in the movie are shown as being members of the 101st Airborne. The problem is the 101st was nowhere near the Malmedy area during any part of the Battle of the Bulge and, indeed, were still in their staging base at Mourmelon, France when the "Malmedy Massacre" took place.