The Battle of Flers–Courcelette (, 15 to 22 September 1916) was fought during the Battle of the Somme in France, by the French Sixth Army and the British Fourth Army and Reserve Army, against the German 1st Army, during the First World War. The Anglo-French attack of 15 September began the third period of the Battle of the Somme but by its conclusion on 22 September, the strategic objective of a decisive victory had not been achieved. The infliction of many casualties on the German front divisions and the capture of the villages of Courcelette, Martinpuich and Flers had been a considerable tactical victory.
The German defensive success on the British right flank made exploitation and the use of cavalry impossible. Tanks were used in battle for the first time; the Canadian Corps and the New Zealand Division fought their first engagements on the Somme. On 16 September, , a specialist fighter squadron, began operations with five new Albatros D.I fighters, which had a performance capable of challenging British and French air supremacy for the first time in the battle.
The British attempt to advance deeply on the right and pivot on the left failed but the British gained about in general and captured High Wood, moving forward about in the centre, beyond Flers and Courcelette. The Fourth Army crossed Bazentin Ridge, which exposed the German rear-slope defences beyond to ground observation. On 18 September, the Quadrilateral, where the British advance had been frustrated on the right flank, was captured.
Arrangements were begun immediately to follow up the success which, after supply and weather delays, began on 25 September at the Battle of Morval, continued by the Reserve Army next day at the Battle of Thiepval Ridge. September was the most costly month of the battle for the German armies on the Somme, which suffered about Combined with the losses at Verdun and on the Eastern Front, the German Empire was brought closer to military collapse than at any time before the autumn of 1918.
Background
Strategic developments
Franco-British At the beginning of August, optimistic that the Brusilov Offensive (4 June to 20 September) on the Eastern Front in Russia, would continue to absorb German and Austro-Hungarian reserves and that the Germans had abandoned the Battle of Verdun, General Sir Douglas Haig, commander of the British Expeditionary Force (BEF) in France, advocated to the War Committee in London, that pressure be kept on the German armies in France for as long as possible. Haig had hoped that the delay in producing tanks had been overcome and that enough would be ready in September.
Despite the small numbers of tanks available and the limited time for the training of their crews, Haig planned to use them in the mid-September battle being planned with the French, in view of the importance of the general Allied offensive being conducted on the Western Front in France, on the Italian front by Italy against the Austro-Hungarians and by General Aleksei Brusilov in Russia, which could not continue indefinitely. Haig believed that the German defence of the Somme front was weakening and that by mid-September might collapse altogether.
By September, Ferdinand Foch the commander of (GAN) and co-ordinator of the Somme offensive, had stopped trying to get the armies on the Somme (Tenth, Sixth, Fourth and Reserve) to attack simultaneously, which had proved impossible and instead make separate sequenced attacks, successively to envelop the German defences. Foch wanted to increase the size and tempo of attacks, to weaken the German defence and achieve rupture, a general German collapse. Haig had been reluctant to participate in August, when the Fourth Army was not close enough to the German third position to make a general attack practicable. The main effort was being made north of the Somme by the British and Foch had to acquiesce, while the Fourth Army closed up to the third position.
To help the Fourth Army, the Reserve Army was to resume attacks against Thiepval and begin attacks into the Ancre river valley; the Fourth Army was to capture the German intermediate and second positions from Guillemont to Martinpuich and then the third position from Morval to le Sars, as the Sixth Army attacked the intermediate line from Le Fôret to Cléry, then the third position from the Somme to Rancourt. On the south side of the river, the Tenth Army would commence its postponed attack from Barleux to Chilly.
German On 28 August, General Erich von Falkenhayn, the Chief of the General Staff of (OHL, supreme army command), simplified the German command structure on the Western Front by establishing two army groups. controlled the 6th Army, 1st Army, 2nd Army and 7th Army, from Lille to the boundary of , from south of the Somme battlefield to beyond Verdun. was dissolved and General Max von Gallwitz reverted to the command of the 2nd Army. The emergency in Russia caused by the Brusilov Offensive, the entry of Romania into the war and French counter-attacks at Verdun, put further strain on the German army. Falkenhayn was sacked from the OHL on 28 August and replaced by Hindenburg and Ludendorff. The Third OHL ordered an end to attacks at Verdun and despatched troop reinforcements to Romania and the Somme front.
Tactical developments
Flers is a village north-east of Albert, south of Bapaume, to the east of Martinpuich, west of Lesbœufs and to the north-east of Delville Wood. The village is on the D 197 from Longueval to Ligny Thilloy. In 1916, the village was defended by the Switch Line, Flers Trench on the western outskirts, Flea Trench and Box and Cox were behind the village in front of Gird Trench and Gueudecourt. Courcelette is near the D 929 Albert–Bapaume road, north-east of Albert, to the north-east of Pozières and south-west of Le Sars.
Since 1 July, the BEF GHQ tactical instructions issued on 8 May had been added to but without a general tactical revision. Attention had been drawn to matters which had been neglected in the heat of battle, such as the importance of infantry skirmish lines being followed by small columns, captured ground being mopped up, avoiding the tendency to rely on hand-grenades (bombs) at the expense of the rifle, consolidation of captured ground, the benefit of machine-gun fire from the rear, the use of Lewis guns on the flanks and in outposts and the value of Stokes mortars for close-support. The wearing-out battles since late July and events elsewhere, led to a belief that the big Allied attack planned for mid-September would have more than local effect.
A general relief of the German divisions on the Somme was completed in late August; the British assessment of the number of German divisions available as reinforcements was increased to eight. GHQ Intelligence considered a German division on the British front was worn-out after days and that German divisions had to spend an average of twenty days in the line before relief. Of six more German divisions moved to the Somme by 28 August, only two had been known to be in reserve, the other four having been moved from quiet sectors without warning.
Hindenburg issued new tactical instructions in ("Principles of Command for Defensive Battles in Positional Warfare") which ended the emphasis on holding ground at all costs and counter-attacking every penetration. The purpose of the defensive battle was defined as allowing the attacker to wear out their infantry, using methods that conserved German infantry. Manpower was to be replaced by machine-generated firepower, using equipment built in a competitive mobilisation of domestic industry under the Hindenburg Programme, the policy rejected by Falkenhayn as futile, given the superior resources of the coalition fighting the Central Powers. Defensive practice on the Somme had already been changing towards defence in depth, to nullify Anglo-French firepower and the official adoption of the practice marked the beginning of modern defensive tactics. Ludendorff also ordered the building of the , a new defensive system behind the Noyon Salient (which became known as the Hindenburg Line) to make possible a withdrawal while denying the Franco-British the chance to fight a mobile battle.
Since July German infantry had been under constant observation from aircraft and balloons, which directed huge amounts of artillery-fire accurately onto their positions and made many machine-gun attacks on German infantry. One regiment ordered men in shell-holes to dig fox-holes or cover themselves with earth for camouflage and sentries were told to keep still to avoid being seen. The German air effort in July and August had mostly been defensive, which led to much criticism from the infantry and ineffectual attempts to counter Anglo-French aerial dominance, dissipating German air strength to no effect. Anglo-French artillery observation aircraft were considered brilliant, annihilating German artillery and attacking infantry from very low altitude, causing severe anxiety among German troops, who treated all aircraft as Allied and came to believe that British and French aircraft were armoured.
Redeployment of German aircraft backfired, many losses being suffered for no result, which further undermined relations between the infantry and (Imperial German Flying Corps). German artillery units preferred direct protection of their batteries to artillery observation flights, which led to more losses as the German aircraft were inferior to their opponents as well as outnumbered. Slow production of German aircraft exacerbated equipment problems and German air squadrons were equipped with a motley of designs until the arrival in August of Jagdstaffel 2 ( [Captain] Oswald Boelcke), equipped with the Halberstadt D.II, which began to restore a measure of air superiority in September and the first Albatros D.Is, which went into action on 17 September.
The tank Development
Before 1914, inventors had designed armoured fighting vehicles and one design had been rejected by the Austro-Hungarian army in 1911. In 1912, Lancelot de Mole, submitted plans to the War Office for a machine which foreshadowed the tank of 1916, that was also rejected and in Berlin an inventor demonstrated a land cruiser in 1913. By 1908, the British army had adopted vehicles with caterpillar tracks to move heavy artillery and in France, Major Ernest Swinton, (Royal Engineers) heard of the cross-country, caterpillar-tracked Holt tractor in June 1914. In October, Swinton thought of a machine-gun destroyer that could cross barbed wire and trenches and discussed it at GHQ with Major-General George Fowke, the army chief engineer, who passed this on to Lieutenant-Colonel Maurice Hankey, the Secretary of the War Council. Little interest had been shown by January 1915. Swinton persuaded the War Office to set up an informal committee which in February 1915 watched a demonstration of a Holt tractor pulling a weight of over trenches and barbed wire, the performance of which was judged unsatisfactory.