The Battle of the Bulge, which occurred from December 1944 until January 1945, was a major German offensive campaign launched through the densely forested Ardennes region of Wallonia in Belgium, France, and Luxembourg on the Western Front at the end of World War II in Europe. The surprise attack caught the Allied forces completely off guard. United States forces bore the brunt of the attack and incurred their highest casualties for any operation during the war. Germany's armored forces on the Western Front became severely depleted, and Germany was largely unable to replace them. German personnel and aircraft in the concluding stages of the engagement also sustained heavy losses.

The phrase "Battle of the Bulge" was coined by the contemporary press covering World War II to describe the way the Allied front line bulged inward on wartime news maps. And so, the name became the most widely used to refer to the battle.

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