Born in Berlin, Germany on 28 February 1833 as the son of a Prussian Army officer. He was part of an old Prussian noble family, the Schlieffen family. He lived with his father, Major Magnus von Schlieffen, on their estate in Silesia, which he left to go to school in 1842. Growing up, Schlieffen had shown no interest in joining the military, so he did not attend the traditional Prussian cadet academies. Instead, he studied at the University of Berlin. While studying law, he enlisted in the army in 1853 for his one year of compulsory military service. After this, instead of joining the reserves, he was chosen as an officer candidate. Thus he started a long military career, working his way up through the officer ranks, eventually completing 53 years of service.
In 1868, fifteen years into his military career, Schlieffen married his cousin Countess Anna Schlieffen. They had one healthy child (Gräfin Elisabeth Auguste Marie Ernestine von Schlieffen, 13 September 1869 - 23 September 1943), but after the birth of a second (Marie, who became a nun), his wife died. After that, Schlieffen focused all his attention on his military work.
On the recommendation of his commanders, Schlieffen was admitted to the General War School in 1858 at the age of 25, much earlier than others. He graduated in 1861 with high honours, which guaranteed him a role as a General Staff officer. In 1862, he was assigned to the Topographic Bureau of the General Staff, providing him with geographical knowledge and a respect for the tactical and strategic value of terrain and weather that would serve him well throughout his career, particularly in the war games he conducted and in the devising of various war plans including the famous Schlieffen Plan. In 1865 he was transferred to the German General Staff proper, though his role was initially a minor one. He first saw active war service as a staff officer with the Prussian Cavalry Corps at the Battle of Königgrätz of 1866, during the Austro-Prussian War. The tactical "battle of encirclement" conducted there was from then on be a constant feature of his tactical doctrine, even as his strategic doctrine consistently favoured the counter-offensive due to both his understanding of terrain and his respect for Clausewitz's assessment of the constantly-diminishing strength of the offensive.
During the Franco-Prussian War, he commanded a small army in the Loire Valley in what was one of the most difficult campaigns fought by the Prussian Army. In France, Frederick I, Grand Duke of Baden, promoted him to Major and head of the military-history division. After years working alongside Helmuth von Moltke and Alfred von Waldersee, on 4 December 1886 he was promoted to Major General, and shortly afterwards, with the retirement of Moltke, became Waldersee's Deputy Chief of Staff. Not long after this he became Quartermeistergeneral, then Lieutenant General on 4 December 1888, and eventually General of the Cavalry on 27 January 1893. In August 1905, at the age of 72, Schlieffen was kicked by a companion's horse, making him "incapable of battle". After nearly 53 years of service, Schlieffen retired on New Year's Day, 1906. He died on 4 January 1913, just 19 months before the outbreak of the First World War. His apocryphal last words are said to have been, "Remember: keep the right wing very strong," (in reference to the main strategic manouevre of Aufmarsch I West), but nobody actually present is known to have said this. Furthermore, the origin of this tale is unknown but only seems to have started appearing several decades after his death.
For Schlieffen, Germany's smaller rate of conscription (55 percent) compared to France's (80 percent) presented a problem. This numerical imbalance was worsened by Russia's 1894 alliance with France. German tactical and operational abilities could not compensate for this quantitive inferiority. It was always Schlieffen's intention to institute genuinely universal conscription and, more importantly, raise as many combat units from trained reservists as possible.
Schlieffen was not in charge of conscription policy; that was the purview of the War Ministry, which in turn was under the budget powers of the Reichstag. Since politics and economics blocked increases in the peacetime army, Schlieffen resorted to creating masses of new units when war came, when he would assume command of the army. Upon mobilisation, large numbers of reservists would be assigned to replacement battalions (Ersatzbataillone), while waiting for an open spot in the field army.
From June 1891 onwards, Schlieffen began to push for transforming Ersatzbataillone into brigade-sized manoeuvre units in the field army. There were major drawbacks to this design. These units were not cohesive, combat-capable forces. Replacement units as field units would also not be able to replace field army casualties. Because the War Ministry had no intention of creating such armed hordes with practically no equipment or command and control, nor was it willing to incur the political cost, it turned down Schlieffen's proposals and nothing was done until 1911, six years after Schlieffen's retirement, when 6 ersatz divisions entered the German order of battle thanks to Ludendorff's efforts. Schlieffen continued to believe in the veracity of his idea and the mass use of Ersatzbataillone in combat formed the keystone of the January 1906 Schlieffen plan Denkschrift. The Schlieffen plan Denkschrift was therefore not a war plan, an impossibility because Schlieffen had retired on 31 December 1905 and the 96 divisions needed to carry out this one-front war plan never existed (in 1914 the German army had 79, of which 68 were deployed in the west), but a demonstration of what Germany might accomplish if she instituted true universal conscription.
Schlieffen thought that even this hypothetical 96-division German army would probably not be able to defeat France in a full-scale strategic offensive:
These preparations [encircling Paris] can be made any way that you like: it will soon become clear that we will be too weak to continue the operation in this direction. We will have the same experience as that of all previous conquerors, that offensive warfare both requires and uses up very strong forces, that these forces become weaker even as those of the defender become stronger, and this is especially true in a land that bristles with fortresses.
Without 12 ersatz divisions on the right flank (in 1914 the German army had only 6 and they were all sent to Lorraine), outflanking Paris was impossible. Schlieffen admitted in the Denkschrift that ersatz units could not catch the right wing by foot-marching nor would the rail system be in a state to support the deployment of 12 ersatz divisions to Paris. If they could not be sent to the right wing, they could be deployed practically anywhere else on the German front, either between Verdun and Mézières, at Metz or on the right bank of the Moselle. There is no evidence that Schlieffen ever conducted an exercise to test a scheme of manoeuvre similar to the one in the Schlieffen plan Denkschrift (a right wing envelopment of Paris), which would be odd indeed if this represented the pinnacle of Schlieffen's strategic thought. None of Schlieffen's surviving deployment plans (Aufmarsch), General staff rides (Generalstabsreisen) or war games (Kriegsspiele) bear any resemblance to the manoeuvre of the "Schlieffen plan". Instead they all point to Schlieffen's counterattack doctrine.
On 11 December 1893 Schlieffen wrote a Denkschrift that represented the completion of his idea of mass warfare. When war came, the German government ought to declare full mobilisation in East Prussia, owing to its vulnerability to Russian cavalry raids. The East Prussian militia would have pre-prepared equipment to defend themselves with. Behind this militia screen the German field army would deploy and then throw back the Russians.
The cornerstone of Schlieffen's war planning was undoubtedly the strategic counter-offensive. Schlieffen was a great believer in the power of the attack in the context of the defensive operation. Germany's smaller forces relative to the Franco-Russian Entente meant that an offensive posture against one or both was basically suicidal. On the other hand, Schlieffen placed great faith in Germany's ability to use her railways to launch a counter-offensive against a hypothetical French or Russian invasion force, defeat it, then quickly re-group her troops and launch a counter-offensive against the other. To quote Holmes:
The Generalstabsreise Ost [eastern wargame] of 1901 followed on from a Generalstabsreise West of the same year, in which the French – not the Germans – attacked through Belgium and Luxembourg and were decisively beaten by a counter-attack on the left bank of the Rhine near to the Belgian border. It was this defensive victory that Schlieffen was referring to when he spoke of the need to crush one enemy first and then turn against the other. He insisted that the Germans 'must wait for the enemy to emerge from behind his defensive ramparts, which he will do eventually'. That was the approach adopted in this exercise, and the Germans won a decisive victory over the French.
Schlieffen also recognised the need for offensive planning, however, as failing to do so would limit the German Army's capabilities if the situation called for them. In 1897, starting from a plan of 1894, Schlieffen developed a tactical plan that – acknowledging the German army's limited offensive power and capacity for strategic manouevres – basically amounted to using brute force to advance beyond the French defences on the Franco-German border. To complement this unsophisticated manoeuvre and improve its chances of success he deemed it necessary to outflank the fortress line to the north and focus on destroying it from north–south starting at Verdun. This was, it must be stated, a tactical plan centred around the destruction of the fortress-line that called for very little movement by the forces involved.
In 1905, however, Schlieffen developed what was truly his first plan for a strategic offensive operation – the Schlieffen plan Denkschrift (Schlieffen plan memorandum). This plan catered for an isolated Franco-German war which would not involve Russia, and more specifically it called for Germany to attack France. The rough draft of this plan was so crude as not to consider questions of supply at all and be vague on the actual number of troops involved, but theorised that Germany would need to raise at least another 100,000 professional troops and 100,000 "ersatz" militiamen (the latter being within Germany's capabilities even in 1905) in addition to being able to count on Austro-Hungarian and Italian forces being deployed to German Alsace-Lorraine to defend it. The German Army would then move through the Dutch province of Maastricht and northern Belgium, securing southern Belgium and Luxembourg with a flank-guard to protect both Germany and the main force from a French offensive during this critical manoeuvre [this being the point of the 1913 French Plan XVII].
But it is here, in the second and final phase of the operation, that Schlieffen shows his true genius: he notes the immense strength of the French "second defensive area" in which the French can use the fortress-sector of Verdun, "Fortress Paris", and the River Marne as the basis of a very strong defensive line. Appreciating its defensive power, Schlieffen knew that he would have to try to force the French back from the Marne or at least secure a bridgehead over the Marne and/or Seine if he did not want the second German operation/campaign of the war to result in heavy losses. To do this, Schlieffen insisted that they cross the Seine to the west of Paris and, if they managed to cross in strength against sufficiently weak opposition, then they might even be able to force the French back from the westernmost sections of the Marne and surround Paris.
However, the bulk of Schlieffen's planning still followed his personal preferences for the counter-offensive. Aufmarsch II and Aufmarsch Ost (later Aufmarsch II West and Aufmarsch I Ost, respectively) continued to stress that Germany's best hope for survival if faced by a war with the Franco-Russian entente was a defensive strategy. This "defensive strategy", it must be noted, was reconciled with a very offensive tactical posture as Schlieffen held that the destruction of an attacking force required that it be surrounded and attacked from all sides until it surrendered, and not merely repulsed as in a "passive" defense:
Discussing the proper German response to a French offensive between Metz and Strasbourg, he insists that the invading army must not be driven back to its border position, but annihilated on German territory, and "that is possible only by means of an attack on the enemy’s flank and rear". Whenever we come across that formula we have to take note of the context, which frequently reveals that Schlieffen is talking about a counter-attack in the framework of a defensive strategy [italics ours].
In August 1905 Schlieffen was kicked by a companion's horse, making him "incapable of battle". During his time off, now at the age of 72, he started planning his retirement. His successor was yet undetermined. Goltz was the primary candidate, but the Emperor was not fond of him. A favourite of the Emperor was Helmuth von Moltke the Younger, who became Chief of Staff after Schlieffen retired.
Moltke went on to devise Aufmarsch II Ost, a variant upon Schlieffen's Aufmarsch Ost designed for an isolated Russo-German war. Schlieffen seems to have tried to impress upon Moltke that an offensive strategy against France could only work in the event of an isolated Franco-German war, as German forces would otherwise be too weak to implement it. Knowing this, Moltke still attempted to apply the offensive strategy of Aufmarsch I West to the two-front war Germany faced in 1914 and Schlieffen's defensive plan Aufmarsch II West. With too few troops to cross west of Paris, let alone attempt a crossing of the Seine, Moltke's campaign failed to breach the French "second defensive sector" and his troops were pushed back in the Battle of the Marne.
Schlieffen was perhaps the best-known contemporary strategist of his time, although criticised for his "narrow-minded military scholasticism."
Schlieffen's operational theories were to have a profound impact on the development of manoeuvre warfare in the 20th century, largely through his seminal treatise, Cannae, which concerned the decidedly un-modern battle of 216 BC in which Hannibal defeated the Romans. Cannae had two main purposes. First, it was to clarify, in writing, Schlieffen's concepts of manoeuvre, particularly the manoeuvre of encirclement, along with other fundamentals of warfare. Second, it was to be an instrument for the Staff, the Waand for the Army all together. His theories were studied exhaustively, especially in the higher army academies of the United States and Europe after the First World War. American military thinkers thought so highly of him that his principal literary legacy, Cannae, was translated at Fort Leavenworth and distributed within the U.S. Army and to the academic community.
Along with the great militarist man we've known Schlieffen to be, there are also underlying traits about Schlieffen that often go untold. As we know, Schlieffen was a strategist. Unlike the Chief of Staff, Waldersee, Schlieffen avoided political affairs and instead was actively involved in the tasks of the General Staff. These tasks included the preparation of war plans, and the readiness of the German Army for war. He focused much of his attention on planning. He devoted time to training, military education and the adaptation of modern technology for the use of military purposes and strategic planning. It was evident that Schlieffen was very much involved in preparing and planning for future combat. He considered one of his primary tasks was to prepare the young officers in not only a way in which they would accept responsibility for taking action in planning manoeuvres, but also for directing these movements after the planning had taken place.
In regards to Schlieffen's tactics, General Walter Bedell Smith, chief of staff to General Dwight D. Eisenhower, supreme commander of the Allied Expeditionary Force in the Second World War, pointed out that General Eisenhower and many of his staff officers, products of these academies, "were imbued with the idea of this type of wide, bold maneuver for decisive results."
General Erich Ludendorff, a disciple of Schlieffen who applied his teachings of encirclement in the Battle of Tannenberg, once famously christened Schlieffen as "one of the greatest soldiers ever."
Long after his death, the German General Staff officers of the Interwar and Second World War period, particularly General Hans von Seeckt, recognised an intellectual debt to Schlieffen theories during the development of the Blitzkrieg doctrine."A man is born, and not made, a strategist."—Schlieffen
"To win, we must endeavour to be the stronger of the two at the point of impact. Our only hope of this lies in making our own choice of operations, not in waiting passively for whatever the enemy chooses for us." — Schlieffen