Germany's plan to knock France out of the war with an early strike had clearly failed by early September 1914. The Allies had halted the German drive toward Paris during the First Battle of the Marne, resulting in a stalemate. The series of battles and engagements that followed would later become known as the Race to the Sea, in which the Germans and Allies took turns attempting to flank each other to the north until they reached the North Sea. With operational-level flanking maneuvers impossible, both sides dug in, creating a long line of opposing trenches and defensive works that reached all the way to the Swiss border. As a result, any progress on the Western Front now required direct assaults on strongly held enemy lines.
Although the Chief of the German General Staff, Erich von Falkenhayn, preferred to keep focusing Germany's offensive actions in the west, several factors combined to force the Germans onto the defensive in the Western Front by late 1914. The development of trench warfare in the west largely removed the possibility of mobile warfare, and the Germans could ill afford to waste precious resources, manpower and artillery shells in difficult and costly assaults on the Allied fortifications. The vast spaces in the Eastern Front, however, continued to allow significant flexibility, preventing a deadlock on the same scale as the one to the west. Also, Gens. Paul von Hindenburg and Erich Ludendorff, heroes of the Battle of Tannenberg, were using their considerable influence to request reinforcements for their planned eastern offensives. Finally, German ally Austria-Hungary was pleading desperately for German help in the east after a series of military reversals inflicted by the Russians and Serbs — as well as the growing possibility of the Italians and Romanians joining the Allies — threatened to overwhelm it. With Germany losing the war in the east and facing serious obstacles in the Western Front, the Germans went on the general defensive in France and Belgium while reserves streamed to the Eastern Front.
The Allies' Position
For the Allies, however, there was little choice but to go on the offensive in the Western Front in late 1914. With Germany now focusing on Russia in the east, the Allies had to relieve the pressure on their Russian allies by attacking the Germans in the west, if only to pin them down and prevent further reinforcements from going eastward. Questions of national pride and prestige, as well as resources, also drove the French onto the offensive. In the early months of the war, the Germans had seized nearly all of Belgium and large areas of northern France — a region rich in coal and iron reserves vital for the war industry — and the Germans were only 60 miles from Paris. They had to be driven back and French territory had to be restored.
By December 1914, and especially after the grueling battles of the Race to the Sea, it was clear the French would have to be the ones to carry out a significant Allied offensive operation, with the British merely in a supporting role. The professional British Expeditionary Force, already very small at the outset of the war, had effectively ceased to exist. The force had deployed 110,000 troops when fighting first broke out, suffering some 95,000 casualties by December 1914. The British Expeditionary Force had to concentrate on rebuilding itself with fresh recruits arriving from the United Kingdom (Kitchener's Army) and overseas colonies. The British would not be able to mount major operations in the west until September 1915, and even then it only had a force of only six divisions.
The French 10th Army kicked off operations in the Artois region Dec. 17, focusing on clearing the Vimy Ridge heights that commanded the Lens-Douai plain. After participating in skirmishes and supporting other French forces in attacks, the French Fourth Army commanded by Gen. Fernand de Langle de Cary joined the attack on Dec. 20 in the Champagne area along a 25-mile line heading toward the Mezieres rail junction. Approximately 260,000 troops assembled for this attack with support from more than 700 artillery pieces.
The German trenches and fortified lines were not as sophisticated as the ones that would cut their way through Belgium and France in the latter years of the war, but they were formidable nonetheless. Barbed wire was laid in front of the trenches, mutually supporting strongpoints were positioned to establish overlapping fields of fire and German artillery was installed to the rear to provide support. With no ability to flank the German positions, the French had no choice but to plan a frontal assault.
The First Battle of Champagne would last until March 1915. It was during the December 1914 punch and counterpunch that the horror of trench warfare became fully apparent to the soldiers on both sides. Advancing French troops expected to find the enemy cut down, or at least suppressed by artillery fire, but instead discovered at a horrible cost that the German trenches were more than adequate to shelter the defending troops from the meager artillery available at that time. Still, German troops packed en masse into the first trench line were vulnerable to direct hits, which would occasionally send a mass of torn flesh and mangled bones into the sky. This resulted in a quick shift of tactics to have a more dispersed and deeper line of defense. Troops from both sides advanced along narrow trenches for fear of being hit by machine gun fire and artillery shrapnel whizzing above. They recounted how they had no choice but to step on the dead and wounded on the bottom of the trench, grinding the bodies down deeper into the mud. The results of the battle were largely inconclusive — but at a great cost to France and Germany.
Both sides learned lessons about trench warfare during the winter battles of 1914-1915 that would shape the next round of trench fighting. Despite its usefulness as a field weapon, the French 75mm gun's shell was found to be too light for trench warfare. This forced the Allies to put greater emphasis on the production of howitzers and heavy trench mortars. The Allies also found that artillery support had to be truly massive to counter the increasingly deep and well-built German trench lines. The limited artillery available during this time — at least until Allied production kicked into high gear and decreased the alarmingly high number of defective shells — would continue to hamstring the Allies in their 1915 offensive operations.
For their part, the Germans quickly realized that positioning most of their available troops in the first defensive trench line was hardly suitable. Instead, they increasingly shifted reserves toward the rear, where they were less vulnerable to massed artillery and could be directed to quickly throw back any Allied gains or potential breaches in vicious counter-attacks. Deeper dugouts to shield troops from heavy artillery fire also became the norm, with secondary and tertiary defensive lines built to the rear and ever more barbed wire laid in front. German artillery also played an increasingly prominent role in counter-battery fire — engaging the enemy's own artillery with indirect fire — as well as accurately massing rounds on Allied infantry advancing across no man's land.
Even with all the dead and wounded, trench warfare had hardly begun. Further lessons would be learned, internalized and applied during subsequent offensives and counteroffensives along the mass line of trenches in the west. Another round of directives would subsequently be issued, applied and modified, only to become quickly outdated and replaced. New weapons, tactics and troops would consequently be introduced to break the stalemate. The Germans, largely on the strategic defensive in the west until 1918, with the exception of an offensive in Verdun, would turn defensive trench warfare into a high science and creative art. The Allies would counter by deploying increasingly heavy and effective artillery, better air support, and troops with new machinery and equipment. The first battles of Champagne and Artois were but the beginning of a long series of increasingly large and deadly offensives that would mark the attritional trench battles characteristic of the Western Front in World War I.