How a rapid series of Allied victories ended the First World War in 1918

History · Published 3 October 2026 Swipe more like this →

In short: The Hundred Days Offensive was not a single planned campaign, but a relentless 95-day sequence of Allied breakthroughs. By shattering the German lines and forcing a retreat to the Hindenburg defenses, the Allies dismantled German morale and military capacity, ultimately compelling the Armistice that concluded the Great War.

Following the exhaustion of the German spring offensive in July 1918, Allied supreme commander Ferdinand Foch seized the initiative. The offensive began on 8 August with the Battle of Amiens, where Allied forces—including British, Canadian, Australian, and French troops—employed over 500 tanks to achieve a decisive surprise. The attack created a 15-mile gap in the German line, leading Erich Ludendorff to label the defeat the Black Day of the German Army. This success demonstrated that the German military, once considered formidable, was suffering from a significant decline in morale and capability.

The strategy shifted toward a series of concentric attacks designed to disrupt German communications and force a withdrawal. By late September, the Allies targeted the Hindenburg Line, a massive defensive network stretching from Cerny to Arras. Following the Battle of St Quentin Canal on 29 September, Allied forces breached the depth of these defenses within a week. General Rawlinson noted that had the German army possessed the strength it held two years prior, these fortifications would have remained impregnable. The subsequent fall of Cambrai on 8 October signaled to the German leadership that the conflict could no longer be sustained.

As the Allies pushed toward the vital Metz-to-Bruges railway, the retreating German forces were forced to abandon vast quantities of heavy equipment and supplies. This logistical collapse accelerated the end of the war, shifting Allied planning from a projected 1919 victory to an immediate conclusion in 1918. Fighting persisted through a series of rearguard actions until the final moments before the 11 November Armistice. The intensity of this final phase, spanning 95 days, fundamentally altered the trajectory of the war and brought the four-year stalemate to a definitive close.

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