The Battle of the Ardennes was one of the opening battles of World War I. It took place from August 21-23, 1914, part of the Battle of the Frontiers. French commander-in-chief Joseph Joffre ordered an attack through the Ardennes forrest in support of the French invasion of Lorraine. The French forces consisting of the Third and Fourth Armies, expecting only light resistance ran into a German advance consisting of the German Fourth and Fifth Armies.
The initial engagement took place in a heavy fog and the Germans built defensive positions before heavy fighting commenced the second day. The French forces were badly routed by entrenched German machine guns, falling back to Verdun and Sedan.

The World War II battle in the same region was called the Battle of the Bulge.

Battle of the Bulge
The Ardennes Offensive, popularly known as the Battle of the Bulge, was the last major German offensive on the Western Front in World War II. Unsuccessful in its goals, it nevertheless tied down huge Allied resources and a slow response to the resulting gap in their lines erased months from their timetable. (An alternative analysis is that the offensive allowed the Allies to destroy the cream of the German Army outside the defenses of the West Wall and in poor supply state, greatly easing the assault on Germany afterward.)

Background
After the failure of Operation Market Garden, the Canadian 1st Army was finally supplied and moved forward, clearing the Westerschelde and opening Antwerp to shipping. This stabilized the lines once again, this time some 125 km to the north of where they had been in early September, and the terrible supply problems the Allies had been having started to ease.

At about this time the massive Soviet Summer 1944 offensive burnt itself out in eastern Poland, and the war paused. Taking advantage of this, Hitler called for ideas to re-open the front in the west. Several ideas were submitted, two rising to the top.

One called for a pincer attack on the US 1st Army under General Courtney H. Hodges, which was overextended and would be easy to surround. An entire army would be cut off in territory that would be fairly easy to defend from counterattack. However this plan would do little to address the overall situation. While removing 1/4 of the Allied fighting force would certainly have an effect, the remaining 3/4s would be more than enough to win the war alone.

Beginning on December 16, 1944, the German forces attacked through the Ardennes Forest in Belgium. The German Wacht am Rhein (Watch on the Rhine) plan for the "Von Rundstedt Offensive" was to split the Allied advance and then cut northwards to seize Antwerp. Since the territory was heavily forested and mountainous, there appeared little chance of an armoured assault in this sector. The battle started in very poor weather; this grounded Allied aircraft and greatly aided the German advance. (This plan can be seen as an attempt to re-create the victory of 1940, which also split the Allied forces in the west by bursting through the Ardennes unexpectedly and trapping the Allied vanguard between a spearhead and the coast.)

The first few days were vital, and although many American troops were over-run or surrendered, unexpectedly strong resistance in certain areas greatly slowed the German advance.

The initial advance was also greatly assisted by surprise. The German General in charge of the offensive Von Rundstedt sent all his orders for the preparation of the attack by motorcycle courier.

On December 21 the German forces had completely surrounded Bastogne, defended by the 101st Airborne Division. When General Anthony McAuliffe was awakened by a German invitation to surrender, he gave a one-syllable reply that has been variously reported and was probably unprintable. However, there is no disagreement as to what he wrote on the paper delivered to the Germans: "NUTS!" That reply had to be explained both to the Germans and to non-American Allies.1

By December 24 the German advance was effectively stalled short of the Meuse River, they had outrun their supply lines, and shortages of fuel and ammunition were becoming critical. Improving weather brought the massive Allied air superiority back into play. The Germans retreated from Bastogne on January 13.

Once the offensive started, the German forces once again relied on their radios, and Intelligence played a major influence in the Allies locating and destroying German units.

The battle officially ended on January 27, 1945.

The Americans lost 75,522 men (killed, wounded, missing or captured), the British lost 1,408 and the Germans lost 67,675 men.

The German losses were critical in reducing the length of the war, vital and irreplaceable men and equipment had been wasted in a few weeks.

1 For the benefit of those not familiar with English slang, Nuts is slang for testicles, but in this context means approximately "go to hell".

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