At Mons, General French's BEF force was facing von Kluck's First Army, which was twice its size. By the afternoon of 23 August, despite their success of earlier in the day, the British regulars were being overwhelmed by sheer numbers. Also, and with the retreat of the the French Fifth Army on their right, they were facing danger of being isolated and annihilated. Orders went out for a withdrawal south, which would continue for two weeks until the BEF was able to escape the German pursuit by crossing and moving south of the Marne river.
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