The 1918 Battle of Soissons forced the German Army onto the defensive for good.

Wars & Conflicts · Published 15 October 2026 · Updated 25 October 2026 Swipe more like this →

In short: Fought from 18 to 22 July 1918, the Battle of Soissons served as a pivotal Allied counter-offensive. By targeting vital German supply lines in the Marne salient, the French, American, and British forces shattered the German momentum, marking the definitive turning point of the First World War on the Western Front.

Following the Russian withdrawal from the war in March 1918, Germany gained a temporary numerical advantage, launching four massive offensives known as the Kaiserschlacht. These attacks created two vast salients, including one in the French sector stretching toward Château-Thierry. By mid-June, Allied command recognized that the communication network at Soissons—a critical junction for railroads and roads supplying German forces in the Marne salient—was the key to forcing a German retreat.

The operation was marked by extreme secrecy. General Mangin, commander of the French Tenth Army, insisted on avoiding preparatory artillery barrages to achieve surprise. American divisions, including the 1st and 2nd, were rushed into position under cover of darkness, often navigating through dense forests and mud without clear maps or coordinated logistics. Despite these challenges, the attack launched on 18 July 1918 behind a rolling barrage, catching German forces off guard despite intelligence reports of a buildup.

The terrain presented significant obstacles, including four deep, swampy ravines and stone-quarried villages that served as German strong points. The American 1st and 2nd Divisions, alongside the Moroccan 1st Division, pushed forward against these defenses. Although the Germans had attempted to reinforce their lines after receiving warnings from deserters, the Allied assault successfully disrupted their supply routes. This victory compelled the German Army to shift to a defensive posture for the remainder of the conflict, effectively ending their hopes for a final victory on the Western Front.

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