The Great Retreat (French: Grande Retraite) also known as the retreat from Mons, took place in the First World War. The retreat was more than 200 km (120 mi), from Belgium to the River Marne in France in August and September 1914. The French Fifth Army and the British Expeditionary Force had been defeated by the armies of the German Empire at the Battle of Charleroi (21 August) and the Battle of Mons (23 August). A counter-offensive by the Fifth Army, with some assistance from the BEF, at the First Battle of Guise (Battle of St. Quentin, 29–30 August) failed to halt the German advance. The retreat of the Fifth Army and the BEF continued to the south side of the Marne River. From 5 to 12 September, the First Battle of the Marne ended the Allied retreat and forced the German armies to retire towards the Aisne River and to fight the First Battle of the Aisne (13–28 September). Reciprocal attempts to outflank the opposing armies to the north known as the Race to the Sea followed from 17 September to 17 October.
Background
Battle of the Frontiers, 7 August – 13 September
The Battle of the Frontiers is a general name for all of the operations of the French armies until the Battle of the Marne. A series of encounter battles began between the German, French and Belgian armies on the German–French frontier and in southern Belgium on 4 August 1914. The Battle of Mulhouse (Battle of Alsace 7–10 August) was the first French offensive of the First World War. The French captured Mulhouse until forced out by a German counter-attack on 11 August, falling back toward Belfort. The main French offensive, the Battle of Lorraine (14–25 August), began with the Battles of Morhange and Sarrebourg (14–20 August) advances by the First Army on Sarrebourg and the Second Army towards Morhange. Château Salins near Morhange was captured on 17 August and Sarrebourg the next day. The German 6th and 7th armies counter-attacked on 20 August, the Second Army was forced back from Morhange and the First Army was repulsed at Sarrebourg. The German armies crossed the border and advanced on Nancy but were stopped to the east of the city.
To the south the French retook Mulhouse on 19 August and then withdrew. On 24 August at the Battle of the Mortagne (14–25 August), a limited German offensive in the Vosges, the Germans managed a small advance, before a French counter-attack retook the ground. By 20 August a German counter-offensive in Lorraine had begun and the German 4th Army and 5th Army advanced through the Ardennes on 19 August towards Neufchâteau. An offensive by French Third Army and Fourth Army through the Ardennes began on 20 August, in support of the French invasion of Lorraine. The opposing armies met in thick fog and the French mistook the German troops for screening forces. On 22 August the Battle of the Ardennes (21–28 August) began with French attacks, which were costly to both sides and forced the French into a disorderly retreat late on 23 August. The Third Army recoiled towards Verdun, pursued by the 5th Army and the Fourth Army retreated to Sedan and Stenay. Mulhouse was recaptured again by German forces and the Battle of the Meuse 26–28 August), caused a temporary halt of the German advance.
Liège was occupied by the Germans on 7 August, the first units of the BEF landed in France and French troops crossed the German frontier. On 12 August, the Battle of Haelen was fought by German and Belgian cavalry and infantry and was a Belgian defensive success. The BEF completed its move of four divisions and a cavalry division to France on 16 August, as the last Belgian fort of the Position fortifiée de Liège surrendered. The Belgian government withdrew from Brussels on 18 August and the Germans attacked the Belgian field army at the Battle of the Gete. Next day the Belgian army began to retire towards Antwerp, which left the route to Namur open; Longwy and Namur were besieged on 20 August. Further west, the Fifth Army had concentrated on the Sambre by 20 August, facing north on either side of Charleroi and east towards the Belgian fortress of Namur. On the left, the Cavalry Corps (General André Sordet) linked with the BEF at Mons.
Prelude
Battle of Charleroi, 21 August
By 20 August, the Fifth Army had begun to concentrate on a 40 km (25 mi) front along the Sambre, centred on Charleroi and extending east to the Belgian fortress of Namur. On the left flank, the Sordet Cavalry Corps linked the Fifth Army to the British Expeditionary Force (BEF) at Mons. General Joseph Joffre ordered Lanrezac to attack across the Sambre but this attack was forestalled by the German 2nd Army on the morning of 21 August, which crossed the Sambre, establishing two bridgeheads which the French, lacking artillery, were unable to reduce. Bülow attacked again on 22 August with three corps against the Fifth Army front. Fighting continued on 23 August, when the French centre around Charleroi began to fall back. The German 3rd Army crossed the Meuse and launched an attack against the French right flank, held by I Corps (General Louis Franchet d'Esperey). The French stopped the German advance and delivered a counter-attack. The Fifth Army was confronted by the German 3rd Army and 2nd Army from the east and the north. Before the Fifth Army could attack over the Sambre the 2nd Army attacked at the Battle of Charleroi and at Namur on 21 August. The 3rd Army crossed the Meuse and attacked the French right flank and on 23 August, the Fifth Army began a retirement southwards, to avoid encirclement.
Battle of Mons, 23 August
The Battle of Mons was a subsidiary action of the Battle of the Frontiers; the BEF attempted to hold the line of the Mons–Condé Canal against the advancing German 1st Army. During 23 August the Germans concentrated on the British at the salient formed by a loop in the canal. At 9:00 a.m., the Germans attempted to cross four bridges over the canal at the salient. By the afternoon the British position in the salient had become untenable; to the east, units of the German IX Corps had begun to cross the canal, threatening the British right flank. At 3:00 p.m. the 3rd Division was ordered to retire from the salient to positions a short distance to the south of Mons. A retreat was ordered towards evening by the 5th Division to conform and by nightfall II Corps had established a new defensive line, running through the villages of Montrœul, Boussu, Wasmes, Paturages and Frameries. The Germans had built pontoon bridges over the canal and were approaching the British positions in great strength. By nightfall on 24 August, the British had retreated to defensive lines on the Valenciennes–Maubeuge road. Outnumbered by the 1st Army and with the French Fifth Army also falling back, the BEF continue to retire. The I Corps retreated to Landrecies and II Corps to Le Cateau. The British suffered 1,642 casualties, the Germans 2,000.
Retreat, 24 August – 1 September
Battle of Le Cateau
On the evening of 25 August, British II Corps commander General Horace Smith-Dorrien, ordered his corps to stand and fight to deliver a stopping blow to the Germans. The Allies set up defensive positions near the town; as I Corps had not arrived, Smith-Dorrien's right flank was unprotected. On the morning of the 26 August, the Germans attacked with two infantry and three cavalry divisions against a British force comprising three infantry divisions, an infantry brigade and a cavalry division. Of the 40,000 Entente troops fighting at Le Cateau, 5,212 men were killed or wounded, c. 2,600 troops were captured and thirty-eight British guns were lost. The Germans suffered 2,900 casualties. As the British retreat continued south towards Paris, there were small, vigorous holding actions by various units of the British rearguard.
Rearguard Affair of Le Grand Fayt
The German 2nd Army commander General Karl von Bülow had ordered a rapid pursuit after the battles of 21–24 August against the French Fifth Army and the BEF. The 1st and 2nd armies were sent to the south-west to gain the left flank of the Allied line. The X Reserve Corps encountered "especially obstinate" resistance at Marbaix and Le Grand-Fayt. On the morning of 26 August 1914, the 2nd Connaught Rangers (2nd Division) under Lieutenant-Colonel A.W. Abercrombie were covering the retreat of the British 5th Infantry Brigade from Petit Landrecies. Unknown to Abercrombie, by late morning the retreat had already taken place but the orders had not been received by the Connaught Rangers.
Hearing the sound of rifle fire coming from near-by Marbaix, Abercrombie set off with two platoons of infantry towards the gunfire only to come under heavy artillery and machine-gun fire. Abercrombie then ordered his force to retire on Le Grand Fayt, which locals had told him was clear of Germans, only to discover that Le Grand Fayt had been abandoned. Abercrombie and his men then came under heavy fire from Germans concealed in the village and the order was given to retreat through the surrounding fields. Despite the heavy German fire and the difficulty of communication in the close terrain, the retreat was carried out in an orderly fashion, although six officers and 280 men were reported as still missing on 29 August, including Abercrombie. By the evening the X Reserve Corps was still near Marbaix and Avesnes. The pursuit by the 2nd Army was ordered to continue on 27 August through Landrecies and Trélon, with the X Reserve Corps advancing towards Wassigny.
Rearguard Affair of Étreux
Bülow had ordered the X Reserve Corps to continue its advance to the south-west, after the encounter at Le Grand-Fayt. The 2nd Royal Munster Fusiliers, had been ordered to hold its ground at all costs, in their first action in France. Less than a battalion strength, just three companies of the 2nd Battalion of the Munsters supported by a couple of field guns engaged the German attackers.
The Munsters fell back to an orchard near Étreux and as night fell on the evening of 27 August, found themselves surrounded; having exhausted their ammunition, they surrendered. In the action at Ètreux, only four officers and 240 other ranks of the 2nd Munsters survived but the Battalion prevented German pursuit of the BEF I Corps, gaining valuable time for the BEF to escape. They were outnumbered at odds of over 6:1 and when finally defeated, the survivors were congratulated by the Germans. The X Reserve Corps had continued its advance towards Wassigny and Étreux on 27 August, where the 19th Reserve Division reported that it had "scattered a British battalion".
Affair of Cerizy
During the morning the 5th Cavalry Brigade moved to the west bank of the Oise about 2 mi (3.2 km) east of Cerizy (Moÿ-de-l'Aisne). Around noon German cavalry appeared on the road from St. Quentin and were engaged by a party of cavalry with a machine-gun 0.5 mi (0.80 km) east of Cerizy supported by a section of Royal Horse Artillery. The party of cavalry was forced back but German attempts to enter La Guinguette Farm were repulsed. In the afternoon, two German cavalry squadrons advanced; the Germans dismounted and then their horses bolted, followed by the riders. The British immediately pursued around the eastern flank and met mounted cavalry near Moy; the 12th Royal Lancers forced the Germans to dismount with rifle fire and stampeded their horses. A squadron of mounted lancers got within 50 yd (46 m), charged and inflicted 70–80 casualties with swords and lances for a loss of five killed. The British gathered c. 30 wounded and estimated that the total German loss was 300 casualties. The Germans had expected to meet a weak infantry detachment and attacked with three dismounted squadrons, intending to charge with three more. The Germans eventually managed to disengage and withdraw behind a hill north of the woods; during the evening the British retired to the south.