The second battle of the Somme, 21 March-4 April 1918, was the first of General Ludendorff’s five great offensives launched during the spring and summer of 1918. At the start of 1918 Ludendorff realised that he had a short period of time in which to win the war – the collapse of Russia gave the Germans a temporary numerical advantage on the Western Front, but millions of American soldiers were on their way to Europe. 318,000 American soldiers were already in France by May 1918, and another million arrived before August.
Ludendorff’s plan involved an attack on a fifty mile front south of Arras. In the south it was intended to reach the Somme, and then hold the line of the river against any French counterattacks. Further north two armies would attack, to the north and south of the Flesquieres salient, created during the battle of Cambrai. The two northern armies would then attack the British position around Arras before advancing north west, to cut off the BEF in Flanders. During the planning process the southern advance was extended to include an advance across the Somme. The success of this southern advance would badly unbalance the entire offensive.
The German attack fell on two British armies. In the north was General Julian Byng’s Third Army, defending the area from Arras south to the Flesquieres salient. To the south was General Hubert Gough’s Fifth Army, which held the line down to Barisis and the junction with the French. The Fifth Army was the weaker of the two armies. At the start of 1918 the BEF had reorganised its divisions, moving from twelve battalion divisions to nine battalion divisions. To avoid disrupting the better divisions in the army, regular divisions were unaffected. Gough’s army, as the newest of the British armies, contained a large number of reorganised divisions. Much of the Fifth Army’s line had only recently been taken over from the French, making it unfamiliar terrain.
The BEF had a wider problem during early 1918. Its last defensive battle had been the second battle of Ypres in 1915. In the intervening years, the only major German offensive on the Western Front had been the battle of Verdun, which had fallen entirely on the French.
Ludendorff assembled a force of seventy one divisions, supported by 6,500 guns and 3,500 mortars, split between three armies and two army groups. From north to south they were Below’s Seventeenth Army and Marwitz’s Second Army, part of the Army Group commanded by Crown Prince Rupprecht, and Hutier’s Eighteenth Army, part of the Army Group commanded by Crown Prince Wilhelm.
The northern part of the German attack was the least successful. Below’s Seventeenth Army east of Arras only advanced two miles during the entire battle, and although it made more progress further south never posed the same threat as the attacks further south. It would take part in the “Mars” attack on 28 March, but once again fail to make any progress against the well established British defences around Arras.
A key element of the German plan was the use of storm trooper tactics. Elite stormtrooper units would lead the attack, advancing through weak points in the British line, bypassing strong points and getting as far behind the British lines as possible. Behind them the regular infantry would mop up the isolated strong points left behind by the artillery bombardment and the stormtroopers. Ludendorff hoped that these tactics would allow his troops to advance five miles on the first day and capture the Allied field guns.
The artillery bombardment began at 4.40 am on 21 March. The bombardment hits targets over an area of 150 square miles, the biggest barrage of the entire war. Over 1,100,000 shells were fired in five hours. A mix of high explosive, poisoned gas and smoke shells were used. The British suffered 7,500 casualties during the bombardment, the front line was badly damaged, communications were cut and the rear zone badly disrupted.
When the infantry assault went in it achieved a stunning success. Most of the British front line fell during the morning, and by the end of the day large parts of the Fifth Army were falling back. Gough was forced to order a fighting retreat to win time for reinforcements to reach his army. At the end of the first day, the Germans had broken through the British first and second lines of defence along a quarter of the entire line attacked. Static trench warfare was about to give way to mobile warfare for the first time since 1914.
The first day of the battle had been very costly for the Germans. They suffered almost 40,000 casualties, slightly more than they inflicted on the BEF. More seriously, the crucial attack in the north had failed to isolate the Flesquieres salient. The German attack was already beginning to head in the wrong direction.
That would have been of little comfort to Gough or the Fifth Army. On 22 March they continued to fall back, losing the last foothold in their original frontline during the day. The biggest retreat was made by XVIII corps, in the middle of Fifth Army, whose commander, General Ivor Maxse, seems to have misjudged an order from Gough for a fighting retreat as allowing him to pull back all the way to the Somme. The biggest danger on 22 March was that the two British armies might become separated – Byng was perhaps too keen to hang on to the Flesquieres salient, won at such cost on the previous day, and Haig had to order him to keep in contact with Gough’s army, even if that required a bigger retreat than the fighting would otherwise justify. The day also saw the first French troops enter the battle, on the south of the line.
On 23 March Ludendorff changed his overall plan for the battle, on the assumption that he had or was about to break through the British lines. Below was to attack to the north west, Marwitz west along the Somme to the north of Amiens and Hutier to the south west to attack the French. Marwitz and Hutier would continue to achieve successes until the end of March, but the original purpose of the attack, the thrust north west against the British, was already fading.
The new focus of the German attack came close to splitting the British and French armies, both physically and in purpose. As the British were forced further east, the need for French reinforcements became increasingly urgent. General Pétain, from whose armies those reinforcements would have to come, was increasingly convinced that the British Fifth Army was beaten. He was also worried about the possibility of a new German attack further east. On 24 March he informed Haig that the French army was preparing to fall back towards Beauvais to protect Paris if the German advance continued. This would have created a massive gap between the British and French armies, and almost certainly forced the British to retreat towards the channel ports, creating a situation very similar to that of 1940.
Alarmed by Pétain’s pessimism, Haig contacted the War Office to request an Allied conference. This took place on 26 March at Doullens, in the line of the German advance. Ten senior Allied politicians and generals were present, including the French president, prime minister and minister of munitions, Generals Pétain, Foch, Haig and Wilson (the Chief of the Imperial General Staff). The end result of the meeting was that General Foch was given overall command of the fighting on the Western Front. It was agreed to hold the Germans east of Amiens. An increasing amount of French soldiers would come to the aid of Gough’s Fifth Army, eventually taking over large parts of the front south of Amiens.
Ludendorff also issued new orders on 26 March. All three of his armies were given ambitious targets, which included the capture of Amiens and an advance towards Compiègne (close to Foch’s own head quarters). Neither of these objectives would be achieved, although Montdidier, half way between the two, would fall on 27 March.
The focus of the German attack changed again on 28 March. This time it was the Third Army, around Arras, that would be the target of Operation Mars. Twenty nine divisions attacked Byng’s army, and were defeated in a day. Mars was cancelled on the same day that it began. The same day saw General Gough replaced as commander of the Fifth Army by General Rawlinson, despite having organised a long and reasonably successful retreat.
The last general German attack came on 30 March. Hutier renewed his assault on the French on the south of the newly formed Somme salient, while Marwitz launched an attack towards Amiens (First battle of Villers-Bretonneux, 30 March-5 April). Some ground was lost, but the German attack was rapidly loosing strength. The Germans had suffered massive casualties during the battle, many to their best units. In some areas the offensive slowed down while German troops looted Allied supply depots.
The final German attack was launched towards Amiens. It came on 4 April, when fifteen divisions attacked seven Allied divisions on a line east of Amiens. At Villers-Bretonneux they came close to capturing the village, but were turned back by an Australian counterattack. An attempt to renew the offensive on 5 April failed. On that day Ludendorff called a halt to the offensive.
Both sides suffered massive losses during the battle. The German official history of 1944 gave a figure of 239,000 casualties. The British suffered 177,739 casualties, 90,882 of them in Gough’s Fifth Army and 78,860 in Byng’s Third Army. The Germans had captured 1,200 square miles of France, and advanced up to 40 miles, but they had not achieved any of their strategic objectives.