So the offensive must be postponed, the subsidiary scheme of August 25 cancelled, the retreat prolonged. General Joffre had left Lanrezac, at noon on the 29th, with the knowledge that an offensive toward St. Quentin was impossible, and during the afternoon had listened to the representations of the British commander, who was accompanied by his three corps commanders and General Allenby. In his report of the interview, French says: “A general retirement on the line of the Marne was ordered, to which the French forces in the more eastern theatre of war were directed to conform,” adding: “Whilst closely adhering to his strategic conception, to draw the enemy on at all points until a favourable situation was created from which to assume the offensive, General Joffre found it necessary to modify from day to day the methods by which he sought to attain this object, owing to the development of the enemy’s plans and changes of the general situation.” It was a hard decision to retreat to the Marne, so abandoning the second great defence line established after the war of 1870, including the forts of La Fère, Laon, and Rheims. This new objective emphasised the dangerous unevenness of the front, for, on the 29th, de Langle’s Army was 40 miles north of the Marne (beyond Rethel), Lanrezac was 50 miles to the north (near Guise), Maunoury and the British were about 30 miles to the north (between Clermont and Compiègne). It was a bold decision. But there was something still more heroic to follow.
Retreat and pursuit now attained their maximum speed, the greatest pressure being always on the west. The city and important railway centre of Amiens was evacuated by d’Amade, and occupied by Kluck’s extreme right, on August 30 (the British base had already been moved to St. Nazaire). On that memorable Sunday, all the roads converging towards Paris were crowded with fugitives, whose panic-haste was only too well justified by the barbarities that marked the progress of the invasion. On the 31st, while the 5th Army was still north of Laon, Kluck was driving across the rearguards of Maunoury and of the British (restored to the general line, after a day’s rest) in the Clermont–Compiègne region. The curvature of the Allied line, and the threat of envelopment on the left, or division of the left from the centre, were acute. As we shall see, however, the enemy had fallen into a more perilous predicament. Paris had begun to be a major factor in the situation. The railways running southward from the capital were overwhelmed with multitudes of flying civilians; so that the detrainment of some of the reinforcements from the east had to be made at a point more distant than had been intended.[40]
The British Commander-in-Chief, conscious of the weakness of his means, but sensible also of what might happen to the great city, now expressed his readiness to take part in a general battle before Paris, provided that his flanks could be covered.[41] But neither of Joffre’s two new armies, the 6th and 9th, was ready for a decisive test. Kluck was hard upon the heels of d’Amade, Maunoury, and the British; and even on the Marne they might not be able to make a stand. Weighing up the possibilities from hour to hour, the Generalissimo concluded that he was not yet justified in risking everything. On September 1, from his headquarters, which were moved on that day from Vitry to a quiet château at Bar-sur-Aube, orders were issued to extend the retreat by another 30 miles to the south banks of the Aube and the Seine. “Despite the tactical successes obtained by the 3rd, 4th, and 5th Armies on the Meuse and at Guise,” he wrote, “the enveloping movement of the left of the 5th Army, insufficiently arrested by the British troops and the 6th Army, obliges the whole of our formation to pivot upon its right. As soon as the 5th Army has escaped the enveloping manœuvre against its left, the mass of the 3rd, 4th, and 5th Armies will resume the offensive.” This order marks the moment at which Verdun became a pivot for the remaining portion of the western retreat. “We shall reach this line,” the Generalissimo added (September 2), “only if we are constrained. We shall attack, before reaching it, if we can realise a disposition permitting the co-operation of the whole of the forces.”
The “General Instruction No. 4” of September 1 indicated, as the turning-point, the line Bray-sur-Seine–Nogent-sur-Seine–Arcis-sur-Aube–Camp-de-Mailly–Bar-le-Duc. By the supplementary note of the following day, this line of arrest was pushed back a little farther still, from Pont-sur-Yonne (south-east of Fontainebleau), through Brienne-le-Château, to Joinville, 25 miles south of Bar-le-Duc. These positions were never reached; but the orders are of great interest, anticipating, as they did, the possibility of a movement that might well have involved the abandonment of Verdun and the creation of a new pivot at Toul–Nancy. Joffre’s public words are so few and sententious that the “General Order No. 11” may be given in full:
“Part of our armies are falling back to re-establish their front, recomplete their effectives, and prepare, with every chance of success, for the general offensive that I shall order to be resumed in a few days. The safety of the country depends upon the success of this offensive, which, in accord with the pressure of our Russian Allies, must break the German armies, that we have already seriously damaged at several points.
“Every man must be made aware of this situation, and strain all his energies for the final victory. The most minute precautions, as well as the most draconian measures, will be taken that the retirement be effected in complete order, so as to avoid useless fatigue. Fugitives, if found, will be pursued and executed. Army commanders will give orders to the depots so that these shall send promptly to the corps the full number of men necessary to compensate for losses sustained and to be foreseen in the next few days.
“The effectives must be as complete as possible, the cadres reconstituted by promotion, and the moral of all up to the level of the new tasks for the coming resumption of the forward movement which will give us the definitive success.
“At General Headquarters, September 2, 1914.
The General Commanding-in-Chief,
“Joffre”