The German General Ludendorff conceived Blücher–Yorck as a massive diversionary tactic to clear the way for a repeated thrust towards the Channel ports. A massive assault was launched on 27 May upon Chemin des Dames ridge, manned by British troops under the French general, Denis Auguste Duchêne. Hoping to avert the storm trooper tactics employed in the recent German operations, Duchêne massed the troops in front line trenches and the heavy bombardment combined with poison gas inflicted devastating casualties. The ridge was recaptured, while further east the Germans smashed through Allied lines near Reims crossing the Aisne within six hours. The momentum continued until 6 June by which time the German army was within shelling distance of Paris. But as with the preceding operations, the combination of overextended supply lines, troop exhaustion and spirited Allied rearguard action ultimately choked off the advance after a final foray from the 15–17 July crossed the Marne at Dormans.
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