Editing Schlieffen Plan (section)

==Prelude==

===Moltke the Younger===
[[File:Generalleutnant von Moltke, der neue Chef des Generalstabs, 1906 (cropped).jpg|thumb|{{center|{{lang|de|Generalleutnant}} Helmuth von Moltke the Younger, Chief of the General Staff, 1906–1914}}]]
[[Helmuth von Moltke the Younger]] took over from Schlieffen as Chief of the German General Staff on 1 January 1906, beset with doubts about the possibility of a German victory in a great European war. French knowledge about German intentions might prompt them to retreat to evade an envelopment that could lead to {{lang|de|Ermattungskrieg}}, a war of exhaustion and leave Germany exhausted, even if it did eventually win. A report on hypothetical French [[riposte]]s against an invasion, concluded that since the French army was six times larger than in 1870, the survivors from a defeat on the frontier could make counter-outflanking moves from [[Paris]] and [[Lyon]] against a pursuit by the German armies. Despite his doubts, Moltke retained the concept of a big enveloping manoeuvre, because of changes in the international balance of power. The Japanese victory in the Russo-Japanese War (1904–1905) weakened the Russian army and the Tsarist state and made an offensive strategy against France more realistic for a time.{{sfn|Foley|2007|pp=72–76}}

By 1910, Russian rearmament, army reforms and reorganisation, including the creation of a strategic reserve, made the army more formidable than before 1905. Railway building in [[Congress Poland]] reduced the time needed for mobilisation and a "war preparation period" was introduced by the Russians, to provide for mobilisation to begin with a secret order, reducing mobilisation time further.{{sfn|Foley|2007|pp=72–76}} The Russian reforms cut mobilisation time by half compared with 1906 and French loans were spent on railway building; German military intelligence thought that a programme due to begin in 1912 would lead to {{cvt|10000|km|order=flip}} of new track by 1922. Modern, mobile artillery, a [[purge]] of older, inefficient officers and a revision of the army regulations, had improved the tactical capability of the Russian army and railway building would make it more strategically flexible, by keeping back troops from border districts, to make the army less vulnerable to a surprise-attack, moving men faster and with reinforcements available from the strategic reserve. The new possibilities enabled the Russians to increase the number of deployment plans, further adding to the difficulty of Germany achieving a swift victory in an eastern campaign. The likelihood of a long and indecisive war against Russia, made a quick success against France more important, so as to have the troops available for an eastern deployment.{{sfn|Foley|2007|pp=72–76}}

Moltke the Younger made substantial changes to the offensive concept sketched by Schlieffen in the memorandum ''War against France'' of 1905–06. The [[6th Army (German Empire)|6th]] and [[7th Army (German Empire)|7th Armies]] with [[VIII Corps (German Empire)|VIII Corps]] were to assemble along the common border, to defend against a French invasion of Alsace-Lorraine. Moltke also altered the course of an advance by the armies on the right (northern) wing, to avoid the Netherlands, retaining the country as a useful route for imports and exports and denying it to the British as a base of operations. Advancing only through Belgium, meant that the German armies would lose the railway lines around [[Maastricht]] and have to squeeze the {{nowrap|600,000 men}} of the [[1st Army (German Empire)|1st]] and [[2nd Army (German Empire)|2nd Armies]] through a gap {{cvt|12|mi}} wide, which made it vital that the Belgian railways were captured quickly and intact. In 1908, the General Staff devised a plan to take the [[Fortified Position of Liège]] and its railway junction by [[coup de main]] on the 11th day of mobilisation. Later changes reduced the time allowed to the fifth day, which meant that the attacking forces would need to get moving only hours after the mobilisation order had been given.{{sfn|Foley|2007|pp=77–78}}

===Deployment plans, 1906–1907 to 1914–1915===
Extant records of Moltke's thinking up to 1911–1912 are fragmentary and almost wholly lacking to the outbreak of war. In a 1906 staff ride Moltke sent an army through Belgium but concluded that the French would attack through Lorraine, where the decisive battle would be fought before an enveloping move from the north took effect. The right wing armies would counter-attack through Metz, to exploit the opportunity created by the French advancing beyond their frontier fortifications. In 1908, Moltke expected the British to join the French but that neither would violate Belgian neutrality, leading the French to attack towards the Ardennes. Moltke continued to plan to envelop the French near [[Verdun]] and the [[Meuse]], rather than an advance towards Paris. In 1909, a new 7th Army with eight divisions was prepared to defend upper Alsace and to co-operate with the 6th Army in Lorraine. A transfer of the 7th Army to the right flank was studied but the prospect of a decisive battle in Lorraine became more attractive. In 1912, Moltke planned for a contingency where the French attacked from Metz to the [[Vosges Mountains]] and the Germans defended on the left (southern) wing, until all troops not needed on the right (northern) flank could move south-west through Metz against the French flank. German offensive thinking had evolved into a possible attack from the north, one through the centre or an envelopment by both wings.{{sfn|Strachan|2003|p=177}}

====''Aufmarsch I West''====
{{lang|de|Aufmarsch I West}} anticipated an isolated Franco-German war, in which Germany might be assisted by an Italian attack on the Franco-Italian border and by Italian and Austro-Hungarian forces in Germany. It was assumed that France would be on the defensive because their troops would be (greatly) outnumbered. To win the war, Germany and its allies would have to attack France. After the deployment of the entire German army in the west, they would attack through Belgium and Luxembourg, with virtually all the German force. The Germans would rely on an Austro-Hungarian and Italian contingents, formed around a cadre of German troops, to hold the fortresses along the Franco-German border. {{lang|de|Aufmarsch I West}} became less feasible, as the military power of the Franco-Russian alliance increased and Britain aligned with France, making Italy unwilling to support Germany. {{lang|de|Aufmarsch I West}} was dropped when it became clear that an isolated Franco-German war was impossible and that German allies would not intervene.{{sfn|Zuber|2010|pp=116–131}}

====''Aufmarsch II West''====
{{lang|de|Aufmarsch II West}} anticipated a war between the Franco-Russian Entente and Germany, with Austria-Hungary supporting Germany and Britain perhaps joining the Entente. Italy was only expected to join Germany if Britain remained neutral. {{nowrap|80 per cent}} of the German army would operate in the west and {{nowrap|20 per cent}} in the east. France and Russia were expected to attack simultaneously, because they had the larger force. Germany would execute an "active defence", in at least the first operation/campaign of the war. German forces would mass against the French invasion force and defeat it in a counter-offensive, while conducting a conventional defence against the Russians. Rather than pursue the retreating French armies over the border, {{nowrap|25 per cent}} of the German force in the west ({{nowrap|20 per cent}} of the German army) would be transferred to the east, for a counter-offensive against the Russian army. {{lang|de|Aufmarsch II West}} became the main German deployment plan, as the French and Russians expanded their armies and the German strategic situation deteriorated, Germany and Austria-Hungary being unable to increase their military spending to match their rivals.{{sfn|Zuber|2010|pp=95–97, 132–133}}

====''Aufmarsch I Ost''====
{{lang|de|Aufmarsch I Ost}} was for a war between the Franco-Russian Entente and Germany, with Austria-Hungary supporting Germany and the [[British Empire]] perhaps joining the Entente. The [[Kingdom of Italy]] was only expected to join Germany if Britain remained neutral; {{nowrap|60 per cent}} of the German army would deploy in the west and {{nowrap|40 per cent}} in the east. France and Russia would attack simultaneously, because they had the larger force and Germany would execute an "active defence", in at least the first operation/campaign of the war. German forces would mass against the Russian invasion force and defeat it in a counter-offensive, while conducting a conventional defence against the French. Rather than pursue the Russians over the border, {{nowrap|50 per cent}} of the German force in the east (about {{nowrap|20 per cent}} of the German army) would be transferred to the west, for a counter-offensive against the French. {{lang|de|Aufmarsch I Ost}} became a secondary deployment plan, as it was feared a French invasion force could be too well established to be driven from Germany or at least inflict greater losses on the Germans, if not defeated sooner. The counter-offensive against France was also seen as the more important operation, since the French were less able to replace losses than Russia and it would result in a greater number of prisoners being taken.{{sfn|Zuber|2010|pp=116–131}}

====''Aufmarsch II Ost''====

[[File:Fond de carte 1914.svg|thumb|{{centre|Map of French, Belgian and German frontier fortifications, 1914}}]]
{{lang|de|Aufmarsch II Ost}} was for the contingency of an isolated Russo-German war, in which Austria-Hungary might support Germany. The plan assumed that France would be neutral at first and possibly attack Germany later. If France helped Russia then Britain might join in and if it did, Italy was expected to remain neutral. About {{nowrap|60 per cent}} of the German army would operate in the west and {{nowrap|40 per cent}} in the east. Russia would begin an offensive because of its larger army and in anticipation of French involvement but if not, the German army would attack. After the Russian army had been defeated, the German army in the east would pursue the remnants. The German army in the west would stay on the defensive, perhaps conducting a counter-offensive but without reinforcements from the east.{{sfn|Zuber|2010|pp=54–55}} {{lang|de|Aufmarsch II Ost}} became a secondary deployment plan when the international situation made an isolated Russo-German war impossible. {{lang|de|Aufmarsch II Ost}} had the same flaw as {{lang|de|Aufmarsch I Ost}}, in that it was feared that a French offensive would be harder to defeat, if not countered with greater force, either slower as in {{lang|de|Aufmarsch I Ost}} or with greater force and quicker, as in {{lang|de|Aufmarsch II West}}.{{sfn|Zuber|2010|pp=52–60}}

===''Plan XVII''===
{{main|Plan XVII}}

[[File:Plan XVII.svg|thumb|{{centre|''Plan XVII''}}]]
After amending ''Plan XVI'' in September 1911, Joffre and the staff took eighteen months to revise the French concentration plan, the concept of which was accepted on 18 April 1913. Copies of Plan XVII were issued to army commanders on 7 February 1914 and the final draft was ready on 1 May. The document was not a campaign plan but it contained a statement that the Germans were expected to concentrate the bulk of their army on the [[Franco-German border]] and might cross before French operations could begin. The instruction of the Commander in Chief was that

{{quote|Whatever the circumstances, it is the Commander in Chief's intention to advance with all forces united to the attack of the German armies. The action of the French armies will be developed in two main operations: one, on the right in the country between the wooded district of the Vosges and the Moselle below Toul; the other, on the left, north of a line Verdun–Metz. The two operations will be closely connected by forces operating on the Hauts de [[Meuse (department)|Meuse]] and in the [[Woëvre]].|Joffre{{sfn|Edmonds|1926|p=446}}}}

and that to achieve this, the French armies were to concentrate, ready to attack either side of Metz–Thionville or north into Belgium, in the direction of [[Arlon]] and [[Neufchâteau, Belgian Luxembourg|Neufchâteau]].{{sfn|Doughty|2005|p=37}} An alternative concentration area for the Fourth and Fifth armies was specified, in case the Germans advanced through Luxembourg and Belgium but an enveloping attack west of the Meuse was not anticipated. The gap between the Fifth Army and the [[North Sea]] was covered by Territorial units and obsolete fortresses.{{sfn|Edmonds|1926|p=17}}

===Battle of the Frontiers===
{{main|Battle of the Frontiers}}
{|class="wikitable" align=right style="margin:0 0 1em 1em"
|+'''Battle of the Frontiers,<br>August 1914'''{{sfn|Doughty|2005|pp=55–63, 57–58, 63–68}}
|-
! Battle
! Date
|-
|[[Battle of Mulhouse]] ||align="right"|7–10 August
|-
|[[Battle of Lorraine]] ||align="right"|14–25 August
|-
|[[Battle of the Ardennes]] ||align="right"|21–23 August
|-
|[[Battle of Charleroi]] ||align="right"|21–23 August
|-
|[[Battle of Mons]] ||align="right"|23–24 August
|}
When Germany declared war, France implemented ''Plan XVII'' with five attacks, later named the [[Battle of the Frontiers]]. The German deployment plan, {{lang|de|Aufmarsch}} II, concentrated German forces (less 20 per cent to defend Prussia and the German coast) on the German–Belgian border. The German force was to advance into Belgium, to force a decisive battle with the French army, north of the fortifications on the Franco-German border.{{sfn|Zuber|2010|p=14}} ''Plan XVII'' was an offensive into Alsace-Lorraine and southern Belgium. The French attack into Alsace-Lorraine resulted in worse losses than anticipated, because artillery–infantry co-operation that French military theory required, despite its embrace of the "spirit of the offensive", proved to be inadequate. The attacks of the French forces in southern Belgium and Luxembourg were conducted with negligible reconnaissance or artillery support and were bloodily repulsed, without preventing the westward manoeuvre of the northern German armies.{{sfn|Zuber|2010|pp=154–157}}

Within a few days, the French had suffered costly defeats and the survivors were back where they began.{{sfn|Zuber|2010|pp=159–167}} The Germans advanced through Belgium and northern France, pursuing the Belgian, British and French armies. The German armies attacking in the north reached an area {{cvt|30|km|order=flip}} north-east of Paris but failed to trap the Allied armies and force on them a decisive battle. The German advance outran its supplies; Joffre used French railways to move the retreating armies, re-group behind the river Marne and the Paris fortified zone, faster than the Germans could pursue. The French defeated the faltering German advance with a counter-offensive at the [[First Battle of the Marne]], assisted by the British.{{sfn|Zuber|2010|pp=169–173}} Moltke the Younger had tried to apply the offensive strategy of {{lang|de|Aufmarsch}} I (a plan for an isolated Franco-German war, with all German forces deployed against France) to the inadequate western deployment of {{lang|de|Aufmarsch}} II (only 80 per cent of the army assembled in the west) to counter ''Plan XVII''. In 2014, Terence Holmes wrote,

{{quote|Moltke followed the trajectory of the Schlieffen plan, but only up to the point where it was painfully obvious that he would have needed the army of the Schlieffen plan to proceed any further along these lines. Lacking the strength and support to advance across the lower Seine, his right wing became a positive liability, caught in an exposed position to the east of fortress Paris.{{sfn|Holmes|2014|p=211}}}}