The Second Battle of Artois (, ) from 9 May to 18 June 1915, took place on the Western Front during the First World War. A German-held salient from Reims to Amiens had been formed in 1914 which menaced communications between Paris and the unoccupied parts of northern France. A reciprocal French advance eastwards in Artois could cut the rail lines supplying the German armies between Arras and Reims. French operations in Artois, Champagne and Alsace from November–December 1914, led General Joseph Joffre, Generalissimo (Commander in Chief) and head of Grand Quartier Général (GQG), to continue the offensive in Champagne against the German southern rail supply route and to plan an offensive in Artois against the lines from Germany supplying the German armies in the north.
Field Marshal Sir John French, commander of the British Expeditionary Force (BEF), co-operated with the French strategy to capture Vimy Ridge by planning British attacks against Aubers Ridge. The attacks would confront the German 6th Army with a joint offensive, on a front, eastwards into the Douai plain, where an advance of would cut the railways supplying the German armies as far south as Reims. The French attacked Vimy Ridge and the British attacked further north in the Battle of Aubers Ridge (9 May) and the Battle of Festubert .
The battle was fought during the German offensive of the Second Battle of Ypres , which the Germans ended to reinforce the Artois front. The initial French attack broke through and captured Vimy Ridge, to the surprise of both sides. German counter-attacks forced them back about half-way to their jumping-off points before French reserves could reach the battlefield. The British attack at Aubers Ridge was a costly failure and two German divisions in reserve were diverted south against the Tenth Army. The British offensive was suspended until 15 May, when the Battle of Festubert began and French attacks from 15 May to 15 June were concentrated on the flanks to create jumping-off points for a second general offensive, which began on 16 June.
The British attacks at Festubert forced the Germans back and diverted reserves from the French but the Tenth Army gained little more ground, despite firing double the amount of artillery ammunition and many more casualties on both sides. On 18 June, the main offensive was stopped and local French attacks were ended on 25 June. The French had regained of territory but their failure to capture Vimy Ridge, despite the expenditure of and the suffering of led to recriminations against Joffre. The defence of the ridge cost the German 6th Army A lull in the area followed until the Third Battle of Artois in September.
Background
Strategic developments
After the Marne campaign in 1914, French offensives in Artois, Champagne and at St Mihiel had been costly failures, leading to criticism of the leadership of General Joseph Joffre, within the army and the French government. The French President, Raymond Poincaré, arranged several meetings between Joffre and the Council of Ministers () in March and April 1915, where reports of the failed operations were debated, particularly a condemnation of the April offensive against the St Mihiel salient. Joffre retained undivided command and freedom to conduct operations as he saw fit, which had been given at the beginning of the war but was instructed to consult with his subordinates; provisional army groups, which had been established in late 1914, were made permanent soon afterwards. The French government accepted that the task facing Joffre and the army was far more difficult than expected, after the winter fighting in Artois and Champagne. Despite costly mistakes, many lessons had been learned, methods had been changed and more weapons and equipment necessary for siege warfare had been delivered. The offensives had failed in their objectives but had become more powerful and better organised, except for the bungled effort at St Mihiel. The greater amount of heavy artillery gave grounds for confidence that further attacks could break the German front and liberate France.
In late 1914, General Erich Von Falkenhayn, Chief of the General Staff (OHL) of the German army since 14 September, had reinforced the 4th Army and attacked westwards, parallel to the North Sea coast, culminating in the Battle of the Yser and the First Battle of Ypres (), when open warfare in the west ended. Eight new divisions were formed in February 1915 and another fourteen in April, which were formed into a new 11th Army, intended for an offensive in France. Despite the French battle in Champagne in February, Falkenhayn was forced to cancel his plans to attack in the west and send the 11th Army to the Eastern Front, to support the Austro-Hungarian army, which has suffered more than by March 1915. Nine divisions were transferred to Russia in May, which reduced the (Western Army) to against French, British and Belgian divisions. The had and field guns, and heavy guns and ten super-heavy howitzers. A reserve of guns and mortars was also being prepared. OHL had divisions in reserve, with the 58th Division and the 115th Division behind the 6th Army. Indications of an attack in Artois had been detected but not signs of a general offensive on the Western Front.
The was forced to remain on the defensive, except for limited attacks in Flanders, in the Second Battle of Ypres () and in the Argonne, west of Verdun, until August to cut the main rail line from Paris to Verdun. In memoranda issued on Falkenhayn ordered that the positions of the German armies in France were to be fortified to resist attacks with only small forces, to enable reserves to be sent to Russia. Should part of the front line be lost, it was to be retaken by counter-attack. Behind the line, new defences were to be built and connected by communication trenches, to delay a further attack until reserves could be assembled for a counter-attack. Opposing reinforcements were to be obstructed by a shell-barrage (). On 4 May, Falkenhayn reiterated the need to improve reserve positions and also to build a rear position about behind the front line. During 1915, the German armies on the Western Front increased the front line from one to three trenches, built a second trench system behind the front line and developed the defensive use of machine-guns and artillery, to restrict an attack to a bend () in the line. The Franco-British offensives in 1915 found the German defences in a state of continuous development, the building programme taking time to complete, due to a shortage of labour.
Tactical developments
In March 1915, Joffre concluded that a period of inactivity would benefit the Germans more than the French; General Ferdinand Foch, commander of the (GPN), proposed an offensive in which a "general action" on the Western Front including the British, to confuse the defenders and pin down reserves, would complement a "decisive action", to break through the German defences at a place where the Germans would not be able to establish a new defensive front by a short retirement. Joffre accepted the proposals on 23 March, with the objective being the seizure of Vimy Ridge and exploitation of the success by an eastwards advance into the Douai plain. The French army had not completed an adaptation to siege warfare and much of the equipment necessary, particularly heavy artillery, did not exist. It had been impossible to synchronise operations in Artois with the First Battle of Champagne, which ended on 17 March. Debate within the army as to means and ends had led to two schools of thought, those, like Joffre, who favoured "continuous battle" (an attack without pause involving all resources) and advocates of "methodical battle" like Foch, who wanted to conduct offensives as methodical series of attacks with pauses to reorganise and consolidate.
The theoretical bases of the forthcoming French offensive in Artois were collected in (Purpose and Conditions for Comprehensive Offensive Action) 16 April 1915 (and Note 5779) which had been compiled from analyses of reports received from the front since 1914. The document contained instructions on infiltration tactics, "rolling" barrages and poison gas, which were to be used systematically for the first time. Although doubtful about the capacity of the British to attack, Joffre wanted an offensive on the northern flank of the Tenth Army, to force the Germans to disperse their defences. At a meeting on 29 March, with Sir John French, the commander of the British Expeditionary Force (BEF), and Herbert Kitchener, the Secretary of State for War, it was agreed that the IX Corps () and XX Corps would be relieved at Ypres by British units and on 1 April, French agreed to attack at the same time as the Tenth Army. French doubts about the efficiency of the BEF had not diminished after the Battle of Neuve Chapelle and British doubts about the French had increased after the at Ypres on 22 April, when French troops had been routed by a German gas attack; Joffre had to agree to place reserves behind the Ypres front to secure British co-operation.
The number of divisions in the German Army was increased over the winter with large intakes of recruits and by reorganising square twelve-battalion divisions (in two brigades with two regiments each) into triangular divisions with one brigade headquarters commanding nine battalions in three regiments. The surplus regiments provided new divisions with a nucleus of trained and experienced troops; smaller divisions made it easier to move them from quiet sectors without undue disruption. On 3 March, Falkenhayn had formed the 11th Army, the (Breakthrough Army) to be the main attacking force on the Western Front. On 30 March, its chief of staff, Colonel Hans von Seeckt, recommended an offensive between Arras and Albert, requiring fourteen corps and artillery batteries. An offensive in the west was cancelled in April, due to the deteriorating situation on the Eastern Front, where the Austro-Hungarian Army (/) faced collapse. The 11th Army and other divisions of the were sent east and the initiative in the west was left with the Entente armies.
The defences of the German army in the west had been improvised since late 1914 and in many places were vulnerable to the growing number of French heavy guns. During the spring, the began to build defences to a standard system, building a second position behind a barbed wire barricade, far enough behind the first position to require an attacker to pause to bring field artillery into range. The first position was elaborated into a zone, with camouflaged strong points and machine-gun nests built of concrete behind the front trenches. The 6th Army held a front of from Menin to the south of Arras with thirteen divisions and the 58th and 115th divisions in OHL reserve behind the front. The 6th Army had guns and guns. West of Lille, the front line was in the marshy Flanders plain and south of La Bassée, the ground was criss-crossed by waterways and drainage ditches, which made fortification difficult. West of Lens, the high ground of Vimy Ridge and the Lorette Spur dominated the ground further to the west; to the south, around Arras, the ground was overlooked from the ridge at Thilloy beyond the Scarpe.
Prelude
French preparations