By 1918, the British blockade forced a near famine on the German population. Imperial Germany would be starved into submission by 1919. However, the peace treaty with the Bolsheviks at Brest-Litovsk formally took Soviet Russia out of the First World War and freed up hundreds of thousands of German troops for the Western Front. Since the early winter, American troops arrived in French ports at the rate of 200,000 a month. Erich Ludendorff, ostensibly known as the First Quartermaster-General of the Imperial German Army but in reality the brains behind the entire German war effort, devised a plan to defeat the British and French before American numbers, and industrial and agricultural capacity could be brought to bear.
Using the divisions released from the Eastern Front, Ludendorff’s offensive sought to split the British and French armies by driving for the English Channel. Once the surrounded British Army was rolled up from the south or its ports captured, the British Army would assuredly surrender, and the French would be forced to sue for peace. The “Kaiserschlacht” or “King’s (Caesar’s) Battle” would consist of three separate offensives: Operation Michael launched on the Somme to split the British and French Armies, Operation Georgette near Ypres to seize the Channel Ports, and Operation Blücher–Yorck to draw French and American reserves south.
The Spring Offensive used “Stormtrooper” tactics perfected against the Russians but on a much larger scale. Whereas previously the best and fittest German troops in a division were specially trained and formed into stormtrooper battalions to infiltrate the enemy trenches and seize strongpoints at the outset of the attack, for the Kaiserschlacht Ludendorff formed entire Stormtrooper divisions. On paper, this seemed a good idea, but actually encouraged the wasteful use of these elite troops against unimportant targets. Being specialist formations, the Stormtrooper divisions forced the basic tactical formation i.e. the lowest level where a single commander controls all of his combined arms formations and specialist attachments, back to the corps level. Since the advent of gunpowder, the basic tactical unit became increasingly smaller: In 17th and 18th century, it was the army. In the 19th, the corps system allowed Napoleon to conquer Europe. By 1918, the smallest combined arms formation was the division. In a First World War division assault zone, not every strongpoint or trenchline was a key piece of terrain, where the stormtroopers were needed. Normally, whatever positions the stormtroopers bypassed were reduced by regular line infantry. By having entire stormtrooper divisions, this forced the elite units to assault positions that could have been taken by regular units, incurring unnecessary casualties and tiring them out. The entire offensive was a gross misuse of a limited resource.
On the foggy morning of 21 March, 1918, Operation Michael unleashed Ludendorff’s Stormtroopers in the Cambrai sector after a short vicious bombardment of key terrain and strongpoints, artillery positions, and Allied command and control centers. In a single day, the Germans recaptured all of the terrain that the British had spent the last three years taking. Within two days, the British Army was in full retreat.
However, the assaults wore down the all-important stormtrooper units. Moreover, the British retreat wasn’t a rout, and the British just withdrew from tactically insignificant terrain, while reinforcing vital areas. Furthermore, Ludendorff “reinforced success”, while nominally a great idea, in the context of the Western Front in 1918, all it lead to were meandering uncoordinated forward advances along paths of least resistance. Within days, the important British defenses had to be reduced by the line divisions (who were stripped of their best men for the stormtroopers) in costly frontal assaults while the exhausted stormtrooper divisions continued the advance over ground mostly abandoned by the British. The Germans had no exploitation force and the speed of a man walking was simply not fast enough to break out before the British and French reacted, who were mostly operating on interior lines (Breakthrough Theory would come to fruition 15 years later with improvements to the tank, motorized transport, and “Blitzkrieg”). The British defended these key points for many reasons, most of which had to do with logistics. While the Germans advanced unprecedented distances which made for great headlines, their supplies couldn’t keep up. Finally, and not insignificantly, the British blockade effectively grounded the German air force for lack of fuel, giving the Allies an immense advantage in reconnaissance.
Operation Michael cost the Allies and Germans 250,000 casualties each, but could not isolate and destroy the British Army. Operation Georgette got to within 15 miles of the Channel ports, but was slowed by last stands from the Portuguese Expeditionary Force, and British, French, and Australian reinforcements that poured in later. Operation Blücher–Yorck was blunted by French and American troops, including the US 1st Division, after some initial success, but failed to draw away significant troops from the main effort, Operation Michael, to the north. In these operations the Allied and German casualties were about the same, a combined 300,000. However, the Allied casualties were replaced in a few months by American troops; the German casualties were irreplaceable, especially in the Stormtroopers divisions who took a disproportionate percentage of losses.
By the end of June, Ludendorff simply ran out of men. There were more in the East which could have been available, but they were “Germanizing” and “civilizing” the vast tracts of Poland, the Baltic States, and Belorussia seized from the Russians. There was no time to reorganize them and bring them west. In July, Ludendorff called off the offensive. The Kaiserschlacht was a body blow to the Allies, but one from which they quickly recovered. The German Army was hollowed out, and unable to conduct further large scale offensives. The conclusion of the war was just a matter of time. The end of The Great War was in sight.