The Western Front, 1918
By the middle of March, 1918, the Germans had transferred 400,000 men from the Eastern to the Western Front and had brought up 80,000 more from Italy. For the first time since September, 1914, the Germans outnumbered the Allies on the Western Front. Ludendorff chose to strike the sector around Saint Quentin, from Arras to Noyon.
The German attack was launched on March 21 with an intense bombardment of the British positions with high explosive and gas shells. The effect of the gas was intensified by a heavy fog, which trapped the gas close to the ground and caused great confusion among the defenders. The German forces made huge advances, pushing the British back to the west side of the Somme. This created a big gap in the Allied line. The Germans poured through, advancing in the open field for the first time since the beginning of trench warfare in 1914.
One reason for the German success was that the Allies lacked unity of command; no one commander had the authority to give orders to both French and British troops so they could work together effectively. Efforts toward a unified command had been made after the Italian defeat at Caporetto in 1917 when the Supreme War Council was formed. This group, however, was a committee of political, not military, leaders and proved ineffective. What was needed was a single supreme commander of all Allied forces in France. This was apparent during the Second Battle of the Somme, when French reserves desperately needed by the British were not forthcoming. On April 14 General Ferdinand Foch was named supreme commander.
When Foch took command the situation appeared desperate. Ludendorff hoped to cut the British and French off from each other by attacking at Amiens, the point where their lines met. The British XIX Corps, which had been driven back 20 miles (32 km) in five days, was in disarray. A brigade was hastily formed from various reserve and support units to bolster it. With the help of these forces, the British finally checked the German penetration.
Fighting died down on April 6. The Germans had won an important tactical victory, advancing 40 miles (64 km) in eight days and inflicting 200,000 casualties. However, they failed to deliver a knock-out blow and lost some of their best troops.
During this crisis General Pershing had offered his forces to Foch for use in any way he might see fit. However, Pershing continued to insist that United States troops must eventually be made into a separate fighting force rather than be used as replacements in British and French divisions.
On March 23 the Germans began a longrange bombardment of Paris using newly developed artillery pieces called "Paris guns," which had a range of about 75 miles (120 km). The bombardment was intended to break the morale of the French. In actuality, it stiffened French resolve to resist the Germans. The battery drew return fire from French railway artillery. The bombardment stopped on May 1, after some 200 rounds had been fired.
Ludendorff launched a fresh attack on April 19 on the Lys River. The attack was originally conceived as a diversionary engagement while the Germans regrouped for another assault against the Allies at Amiens. However, initial successes led Ludendorff to conclude that there was an opportunity to break through to the Channel ports. He threw in his reserves without restraint. The British, with some French reserves, put up fierce resistance. Ludendorff called off the attack on April 29, deciding that further efforts in this area would be too costly.
Ludendorff knew that with every passing day, more American troops were arriving in France. Though the spring rains made the terrain difficult, Ludendorff could not wait until summer. He decided to attack the Allies at the Aisne River, south of Laon. The attack began on May 27 and Soissons fell two days later. This broke a hole in the Allied lines. The Germans rushed through, occupying a salient 30 miles (48 km) deep and 35 miles (56 km) wide at the base.
The narrowness of this salient left it susceptible to the danger that simultaneous attacks at each end might succeed at cutting the main assault force from its support. As a result, Ludendorff began the Friedensturm, or peace offensive, an attack intended to widen the salient. Ludendorff hoped to break through the Allied line and advance to the Marne. From there, the Germans could march on Paris.
Efforts to take Reims at the close of May were unsuccessful. Ludendorff then prepared a major blow intended to eliminate the Allied salient from Chteau-Thierry to Montdidier. On June 9 he threw 15 divisions against the French in this sector, but Foch was prepared and offered steady resistance.
There had been some question about the quality of the hastily trained United States troops. During this period all doubts on this point were removed. The U.S. First Division entered the trenches in front of Cantigny on May 28. Here under Major General Robert L. Bullard they charged the enemy line and took the town.
When the German drive began sweeping down to the Marne, two other United States divisionsthe Second and Thirdwere thrown against this tide, meeting it at Chteau-Thierry. The German advance was checked and on June 6 a brigade of U.S. Marines of the Second Division began a series of attacks on Belleau Wood. After terrible losses, the Marines took the position on June 26.
The fourth and final German lunge for victory began July 15. The Germans crossed the Marne from Dormans to a point west of Jaulgonne. They made some advances against the Allied positions, but again failed to break through. This marked the end of Germany's offensives. Supplies and reserves were scarce and morale was low. Ludendorff realized this and pulled his troops back into a defensive position.
Foch lost no time in taking the initiative. There were now more than a million United States troops in France, and more were arriving at the rate of almost 300,000 a month. The Allies had regained the advantage of superior numbers. On July 18, with the support of a large number of tanks, French and American troops under General Charles Mangin delivered a sudden attack on the exposed German flank between the Aisne and Chteau-Thierry. They took 20,000 prisoners and forced the Germans to retreat across the Marne.
Foch brought continual pressure against the Germans. French, British, American, and Italian troops attacked on both sides of the Marne salient. They cut off the German troops in the salient from their support, ending the danger of a German attack on Paris.
Foch then planned two attacks, one by the British to clear Amiens and one by the Americans to clear the St. Mihiel salient. Ludendorff began a withdrawal to the Hindenburg Line.
General Haig was in command of the attack on a 30-mile (48-km) sector from Amiens to Montdidier. His forces were composed of the British Fourth Army and the French First Army. The Fourth Army was largely made up of Canadians and Australians. Some 400 tanks took part in the engagement. Expecting an attack elsewhere, the Germans were completely surprised when the Allies moved forward on the morning of August 8. On the first day, they advanced from four to seven miles (6 to 11 km), capturing 16,000 troops. Many of them simply threw down their weapons and surrendered. This event was so devastating to German morale that Ludendorff referred to August 8 as "the black day" for the German armies.
General Georges Humbert's Third French Army struck near Montdidier August 9. The Germans were again surprised. In a day and a half the French advanced eight miles (13 km), cut the road to Roye, and took Montdidier.
During the next five days the Allies continued to drive the Germans back. By August 15 the British were only two miles (3 km) from Chaulnes and the French four miles (6 km) from Roye. In a week the Germans had lost 30,000 prisoners, and probably as many more were killed and wounded. Also, desertions rose enormously.
German difficulties were increased by a brilliant French attack on the line from Noyon to Soissons on August 20. Mangin advanced to the western end of the Chemin-des-Dames, taking large numbers of prisoners. The British pushed onward, also, attacking on the old Somme front. They struck at the Hindenburg Line and captured the Drocourt-Queant railway line. The German armies were beginning to show signs of exhaustion.
Meanwhile, the role of the American Expeditionary Force was growing. On August 10, United States units were grouped together to form the United States First Army. In the beginning of September, it went into the line east of Verdun, covering about 50 miles (80 km) of the front, including the St. Mihiel salient.
The area around St. Mihiel was a well-defended bulge in the German line that prevented an Allied advance on Sedan. Pershing massed his troops around the salient. German commanders sensed the impending attack and began a slow withdrawal. During this withdrawal, on September 12, the American troops attacked, supported by British and French artillery. The retreating Germans made little effort to defend the salient. Within one day, Pershing's troops captured the salient, 15,000 prisoners, and the Paris-Avricourt double-track railway. The battle was the first victory by the United States First Army.