The First World War

by Hew Strachan

Bülow had already decided that the 1st and 2nd Armies should retreat on converging lines. Whereas he was preoccupied with the dangers presented by an enemy breakthrough, Kluck was focused on the opportunities for victory presented by envelopment : the one was the obverse of the other, since Kluck’s pursuit of envelopment was what opened the opportunities for an allied breakthrough. When Hentsch at last arrived at Kluck’s headquarters after a five-hour drive on crowded roads on the morning of the 9th, Kluck himself was out of contact, pushing the attack on the French 6th Army. Hentsch and Kluck’s chief of staff therefore took the responsibility for ordering the 1st Army’s retreat. Kluck liked to maintain that he was on the verge of defeating the 6th army, but such an argument leaves out of account any effects that the BEF’s advance would have had as it hit his army on its left and rear. The Germans fell back to the heights overlooking the Aisne valley, where they entrenched.