I. French and d’Espérey strike North
The unescapable dilemma of the Joffrean strategy had developed into a second and peremptory phase. In deciding to withdraw from the Brie plateau and the Marne, rather than risk his rear and communications for the chance of a victory on the Seine, Kluck, or his superiors, had, doubtless, chosen the lesser evil. The marching wing of the invasion was crippled before the offensive of the Allies had begun; but Gallieni’s precipitancy had brought a premature arrest upon the 6th Army. Beside this double check, we have now to witness a race between two offensive movements—Bülow and Hausen pouring south with the impetuosity of desperation, while, along their right, the British Force and the French 5th Army struck north between the two western masses of the enemy with the fresh energy of an immense hope. Which will sooner effect a rupture?
Logically, there should be no doubt of the answer. Kluck was mainly occupied with Maunoury; Bülow, with Foch. Between them, there was no new army to engage the eight corps of Sir John French and Franchet d’Espérey. The cavalry and artillery force of Marwitz and Richthofen, strong as it was, could do no more than postpone the inevitable—always provided that Maunoury and Foch could hold out. Every day, the pull of Kluck to the north-west and of Bülow to the south-east must become more embarrassing. French writers have applied an expressive phrase to the influence of this pull—“effet de ventouse,” effect of suction—though hardly appreciating its double direction. The maintenance of a continuous battle-line is axiomatic in modern military science. It follows from the size of the masses in action, the difficulty, even with steam and petrol transport, of moving them rapidly, and their dependence upon long lines of supply. The soldier bred upon Napoleonic annals may long for the opportunity of free manœuvre; all the evolution of warfare is against his dream. An army neither feeds nor directs itself; it is supplied and directed as part of a larger machine executing a predetermined plan. Superiority of force is increased by concentration, and achieves victory by envelopment of the enemy as a whole, or his disintegration by the piercing of gaps, a preliminary to retail envelopment or dispersal. A course which loses the initial superiority and requires a considerable change of plan is already a grave prejudice; when to this is added a necessary expedient leading to an extensive disturbance of the line, prudence dictates that the offensive should be suspended until the whole mass of attack has been reorganised in view of the new circumstances. The German Command dare not risk such a pause. It persisted; and the penalty lengthened with every hour of its persistence. The more Kluck stretched his right in order to cover his communications by Compiègne and the Oise valley, the wider became the void between his left and the II Army, constantly moving in the opposite direction. When French and d’Espérey found this void, a like difficulty was presented to Bülow—to be enveloped on the right, or to close up thither, leaving a breach on his other flank, which the Saxon Army would be unable to fill. Thus, Maunoury’s enterprise on the Ourcq, though falling short of full success, produced a series of voids, and, at length, a dislocation of the whole German line, which was only saved from utter disaster by a general retreat.
Opening of the ALLIED OFFENSIVE
British Front & D’Espérey’s Left
Sept. 6, 6 a.m.
General Franchet d’Espérey, who had been brigadier in 1908, divisional commander in 1912, a gallant and energetic officer now fifty-eight years of age, successful with the 1st Corps at Dinant and St. Gerard in Belgium, and in the important battle of Guise, had, on September 3, succeeded Lanrezac at the head of the largest of the French armies, the 5th. Its task—in touch with Foch on the right, and with the British, through Conneau’s cavalry corps, on the left—was to press north toward Montmirail, against Kluck’s left (III and IX Corps, and Richthofen’s cavalry divisions) and the right wing of Bülow (VII Corps and X Reserve Corps). In later stages of the war, the junction of two armies often showed itself to be a point of weakness to be aimed at. With four active corps and three divisions of reserves in hand, d’Espérey had, even before the German withdrawal began, a considerable advantage—indicating Joffre’s intention that it should be the second great arm of his offensive, that which should make the chief frontal attack. On the other hand, the enemy held strong positions along the Grand Morin, and, behind this, along the Vauchamps–Montmirail ridge of the Petit Morin. During their retreat the Allies had used the opportunity offered by the valleys of the Marne and its tributaries for delaying actions; these streams were now so many obstacles across their path. The first French movement, on September 6, was powerfully resisted. On the left, the cavalry occupied Courtacon.[63] At the centre, the 18th and 3rd Corps co-operating (prophetic combination—Maud’huy, Mangin, and Petain!), the villages of Montceaux-les-Provins and Courgivaux, on the highroad from Paris to Nancy, which was, as it were, the base of the whole battlefield, were taken by assault. On the right, the 1st Corps was stopped throughout the forenoon before Chatillon-sur-Morin by the X Reserve Corps. D’Espérey detached a division, with artillery, to make a wide detour and to fall, through the Wood of La Noue, upon the German defences east of Esternay. Thus threatened, the enemy gave way; and the market-town of Esternay was occupied early on the following morning. The 10th Corps continued the line toward the north-east, after suffering rather heavy losses beyond Sezanne.
On the morning of September 7, the air services of the 5th Army reported the commencement of Kluck’s retreat; and soon afterwards a corresponding movement of Bülow’s right was discovered to be going on behind a screen of cavalry and artillery, supported by some infantry elements. D’Espérey had no sooner ordered the piercing of this screen than news was brought in of the critical position of the neighbouring wing of Foch’s Army, the 42nd Division and the 9th Corps, through which Bülow’s X and Guard Corps were trying to break, from the St. Gond Marshes toward Sezanne. He at once diverted his 20th Division to threaten the western flank of this attack (which will be followed in the next section) about Villeneuve-lès-Charleville. Meanwhile, rapid progress was being made on the centre and left of the 5th Army. Between Esternay and Montmirail extend the close-set parklands called the Forest of Gault, with smaller woods outlying, a difficult country in which many groups of hungry German stragglers were picked up during the following days. Through this district, the 1st Corps and the left of the 10th, with General Valabrègue’s three divisions of reserves behind, beat their way; while, farther west, in the more open but broken fields between the Grand and the Petit Morin, the 18th and the 3rd Corps made six good miles, to the line Ferté Gaucher–Trefols. More than a thousand prisoners were taken during the day, with a few machine-guns and some abandoned stores.
We have seen (pp. 124–5, 131) the British Expeditionary Force at the beginning of a like novel and exhilarating experience. Its five divisions, having seized Coulommiers on the night of September 6, had pressed on to the Petit Morin, and, from its junction with the Marne eastward to La Trétoire, where obstinate opposition was offered, had secured the crossings. D’Espérey’s left wing thus found its task lightened; and the 18th and 3rd Corps were ordered to sweep aside the remaining German rearguards, and to strike across the Petit Morin on either side of Montmirail. September 8 was thus a day rather of marching than fighting, except at Montmirail, on whose horse-shoe ridge the enemy held out for some hours.[64] In the evening, General Hache entered the picturesque town, and set up his quarters in the old château where Bülow’s Staff had been housed on the previous day. On the left, Maud’huy pushed the 18th Corps by Montolivet over the Petit Morin, and after a sharp action took the village of Marchais-en-Brie. On the right, the 1st Corps was checked at Courbetaux and Bergères, the German VII Corps having come into line; so that the 10th Corps, between Soigny and Corfelix, had to turn north-westward to its assistance. This was scarcely more than an eddy in the general stream of fortune. The moral effect of a happy manœuvre goes for much in the result. The British and d’Espérey’s men forgot all their sufferings and weariness in the spectacle of the enemy yielding. British aviators reported Kluck’s columns as in general retreat, certain roads being much encumbered. Bülow had necessarily withdrawn his right to maintain contact; his centre and left must follow if the pressure were continued.
The hour of decision approached. During the morning of Wednesday, September 9, Sir John French’s 2nd and 1st Corps crossed the Marne at Luzancy, Sââcy, Nanteuil, Charly, and Nogent-l’Artaud. This part of the valley was scarcely defended; and a brigade of the 3rd Division had progressed 4 miles beyond it by 9 a.m. Anxious news for the German Staff. Unfortunately, our right was arrested until afternoon by a threat of attack from Château-Thierry; and, lower down the river about La Ferté, the 3rd Corps, still represented only by the 4th Division and the 19th Brigade, was stopped until evening before the broken bridges and rifle-parapets on the northern bank. Some guns then carried over near Changis bombarded the German artillery positions beyond the Ourcq, a notice to quit that had prompt effect. Château-Thierry was left to the French 18th Corps, which occupied the town that night. Meanwhile, Smith-Dorrien and Haig entered the hilly country about Bezu, Coupru, and Domptin, on the road from Château-Thierry to Lizy-sur-Ourcq. Marwitz vainly essayed to obstruct the northward movement. Beaten in an action near Montreuil-aux-Lions, he informed Kluck that he could do no more, and hurried back to the line of the little river Clignon, about Bussiares and Belleau, which were reached by 4 p.m. A little later, British Aviators brought in word that the enemy had evacuated the whole angle between the east bank of the Ourcq and the Marne, and that, on the other hand, the withdrawal of the German I Army was creating a void beyond Château-Thierry: the cavalry of Richthofen, sent thither by Bülow, was in the same predicament as that of Marwitz farther west. At daybreak on September 10, Pulteney’s Corps left the Marne behind. Meeting no serious resistance, the British crossed the Clignon valley, and by evening occupied La Ferté-Milon, Neuilly-St. Front, and Rocourt.
These were marching days for the 5th Army. Conneau’s cavalry, reinforced by an infantry brigade and extra batteries, passed the Marne at Azy on the 9th, and, harrying Bülow’s right flank, reached Oulchy-le-Château next day. The 18th Corps, with the reserve divisions in support, pushed on from Château-Thierry toward Fère-en-Tardenois; and the 3rd Corps, which had occupied Montigny, half-way between Montmirail and the Marne, on the 9th, forced the passage, under heavy fire from the hills at Jaulgonne, on the 10th. The 1st Corps had a heavier task. Having progressed as far as the Vauchamps plateau, it was wheeled back to the south-east to help the 10th Corps, which d’Espérey had transferred to Foch’s Army of the centre, now in the gravest peril.