The First World War

by John Keegan

  So, it must be said, did Schlieffen; but he, a pupil of Moltke’s system of staff education, understood only its disciplines, not its inspiration. Moltke, while insisting on rigour in military analysis, had always taken trouble to adjust his strategic ideas to the spirit of his country’s diplomacy. He and Bismarck, whatever their differences over policy, opened their minds to each other. Schlieffen was uninterested in foreign affairs. He believed in the primacy of force. Because of the young German Kaiser’s ill-judged repudiation of Bismarck’s “reinsurance” treaty with Russia in 1890, a treaty holding Russia to neutrality with Germany unless Germany attacked France, and Germany to neutrality with Russia unless it attacked Austria-Hungary, Germany’s ally, he was allowed, on succeeding as Chief of Staff, to give his preoccupation with force full rein.15 Chess-board thinking came to possess him. The pieces he identified were few: a France weaker than Germany but protected by forts, a Russia weaker than Germany but protected by great space; a weak Austrian ally, but hostile to Russia and therefore useful as a distraction and perhaps even as a counterweight; a very weak Italy, allied to Germany and Austria, which therefore did not count; a Britain which could be ignored, for Schlieffen was so uninterested in seapower that he even despised the German navy, darling of the Kaiser though it increasingly became during his reign.16

  Given the relativities of force, and they alone influenced his thinking, he arrived in progressive stages at a plan to commit seven-eighths of Germany’s strength, in the contingency of war, to an overwhelming offensive against France, an all-or-nothing endgame that risked his own king in the event of failure. Schlieffen, however, discounted failure. Already by August 1892 he had decided that the west, not the east as in Moltke’s and Waldersee’s thinking, must be the centre of effort. By 1894 he was proposing a scheme for destroying the French fortresses along the Franco-German frontier. In 1897, having accepted that Germany’s heavy artillery could not do sufficient damage to the forts, he began to argue to himself that the “offensive must not shrink from violating the neutrality of Belgium and Luxembourg,” in other words, neutralising the French fortresses by outflanking them. Plans written between 1899 and 1904, tested in war games and staff rides, envisaged an advance through Luxembourg and the southern tip of Belgium with more than two-thirds of the army. Finally, in the so-called “Great Memorandum” of December 1905, completed just before his retirement after fourteen years in the highest military post, he cast moderation aside. Belgian neutrality—guaranteed jointly by Britain, France and Prussia, since 1839—was not tepidly to be infringed but violated on the largest scale. Almost the whole of the German army, drawn up on a line hinged on the Swiss frontier and reaching nearly to the North Sea, was to march forward in a huge wheeling movement, first through Belgium, the outer wing to pass north of Brussels, then across the plains of Flanders to reach, on the twenty-second day after mobilisation, the French frontier. On the thirty-first day, the German line was to run along the Somme and Meuse rivers and from that position the right wing was to turn southwards, envelop Paris from the west and begin to drive the French army towards the left wing advancing from Alsace-Lorraine. A great semi-circular pincer, 400 miles in circumference, the jaws separated by 200 miles, would close on the French army. Under inexorable pressure the French would be pinned to the ground of a decisive battlefield, fought to a standstill and crushed. By the forty-second day from mobilisation, the war in the west would have been won and the victorious German army freed to take the railway back across Germany to the east and there inflict another crushing defeat on the Russians.17

  The Schlieffen Plan

  Schlieffen continued to tinker with his plan, even in retirement, until his death in 1912. He had no other occupation. He was a man without hobbies. As Chief of Staff he had often worked until midnight, then relaxed by reading military history to his daughters. Military history was a subordinate passion to writing war plans. He had been the Great General Staff’s military historian before becoming its chief, but studied history in a wholly technical way. It was the dispositions of armies on a map that interested him, not the spirit of their soldiers, nor the reasoning of governments that had brought them to the clash of arms.18 He had an obsession with Cannae, the battle in which Hannibal had encircled the Roman legions in 216 BC. Hannibal’s crushing victory was a major inspiration of his Great Memorandum of 1905. In Cannae he perceived the pure essence of generalship, untainted by politics, logistics, technology or the psychology of combat. His practical service as a young officer with the Lancers of the Guard seems to have left no mark; in the wars of 1866 and 1870 he was already on the staff: by 1884 he was a professional military historian; after 1891 the routines of the map table appear to have possessed him completely. Aloof, sarcastic, intellectually arrogant, ever more olympian as his tenure of office extended to its unprecedented duration, he had by the end of his career succeeded in reducing war, at least for himself, to a pure abstraction, so many corps here, so many there. An extract from the Great Memorandum gives the flavour:

  If possible, the German Army will win its battle by an envelopment with the right wing. This will therefore be made as strong as possible. For this purpose eight army corps and five cavalry divisions will cross the Meuse by five routes below Liège and advance in the direction of Brussels-Namur; a ninth army corps (XVIIIth) will join them after crossing the Meuse above Liège. The last must also neutralise the citadel of Huy within whose range it is obliged to cross the Meuse.

  Odder still, given his obsession with troop movements, Schlieffen had no interest in enlarging the size of the German army so as to ensure its capacity to overwhelm the enemy. As Holger Herwig has recently argued, he shared a prevailing fear of the Prussian Generalität that expansion would corrupt an army of apolitical country lads with socialists from the big cities.19 Though in 1905 he demanded the raising of thirty-three new infantry battalions, that was because he had calculated such a number to be the shortfall threatening his plan with failure. He wanted at that stage no more, though Germany’s large and expanding population of young men could easily have supplied it. The intellectual problem he had set himself, and believed he could solve, was how to win a short war with the resources available. His ambition was to repeat the triumphs of the great von Moltke in 1866, against Austria, and 1870, against France, wars of six and seven weeks respectively. Above all he wanted to avoid a “wearing-out” war. “A strategy of attrition,” he wrote, “will not do if the maintenance of millions costs billions.”20

  He did not live to discover, as Hitler would, that brilliant schemes of aggression, if flawed, entail attrition as if by an inexorable reactive law. Yet Schlieffen was, within the circumstances his own time imposed, right to limit numerically the scope of the offensive he devised. Hitler’s scheme was to fail because, after a whirlwind victory in the west, he persuaded himself that he could repeat victory in the vast spaces of the east. Schlieffen shrank from those spaces. He recognised that a marching army of foot and horse would exhaust its impetus in the limitless room of the steppe. Hence his midnight vigils over the maps of Flanders and the Ile-de-France, a corps here, a flank march there, a river bridged, a fortress masked. His midnight pettifoggery had as its object an exact adjustment not of German numbers to those that the French could deploy, but to what the Belgian and French road network could carry. Such calculations were the groundwork of staff-college training: students, transferring from prepared tables the length of a marching column—twenty-nine kilometres for a corps, for example—to a road map, could determine how many troops could be pushed through a given sector at what speed. Since thirty-two kilometres was the limit of a forced march, that would be the advance of a corps on a single road; but the tail of a column twenty-nine kilometres long would remain near or at the marching-off point at the day’s end. If there were twin parallel roads, the tails would advance half the distance, if four three-quarters, and so on. Ideally, the units of a corps would advance not in column but in line abreast, allowing all of it to arrive at t
he day’s end thirty-two kilometres further on; in practice, as Schlieffen admitted in one of his amendments, parallel roads were at best to be found one to two kilometres apart. As his great wheeling movement was to sweep forward on a front of three hundred kilometres with about thirty corps, however, each would have only ten kilometres of front on which to make its advance, in which there might at best be seven parallel roads. That was not enough to allow the tails of the columns to catch up with the heads by the day’s end. The drawback was serious in itself; more seriously, it absolutely forbade any attempt to crowd more troops into the radius of the wheeling movement. They would not fit; there simply was not room.21

  Schlieffen’s determination to work with the numbers he had was therefore correct; the plan derived from mathematical realities. As he recognised in his final amendment, any attempt to increase numbers on the roads, perhaps even to work with the numbers in hand, would result in a useless traffic jam: “an unnecessary mass will be formed behind the firing-line.”22 The plan, unfortunately for the Germans, was not, however, derived purely from mathematical realities. Its ultimate wellspring was wishful thinking. Schlieffen had a dream of repeating the great victories of 1870, not as then on the Franco-German frontier, for he realised that the French were unlikely to do Germany the “willing favour” of plunging a second time headfirst into its territory, but deep inside France itself. Yet France, as he emphasised time again and again, was a “great fortress,” fortified on its frontiers and in its interior, fortified above all at Paris, a city surrounded by modern fortifications. Belgium, though fortified also, offered a way round the French frontier forts, for its army was too small to resist German strength for any period; but to pass through Belgium towards Paris both lengthened and narrowed the front of advance. Hence the obsession with the road network, the search for a corridor through Flanders to the Ile-de-France and Paris down which the corps of the right wing could crowd fast enough to reach the field of decisive battle within the time limit of six weeks from mobilisation day; longer than that and the Russians would have emerged from their great spaces to overwhelm the exiguous forces left in the east to defend the approaches to Berlin.

  The dream was of a whirlwind; the calculations warned of a dying thunderstorm. Even in the Great Memorandum of 1905 Schlieffen took counsel of his fears. “It is therefore essential,” he wrote, “to accelerate the advance of the German right wing as much as possible” and “the army commanders must be constantly on the alert and distribute the marching routes appropriately”; this when, by his own admission, the median marching speed of trained troops was twenty kilometres a day.23 Orders to speed up or to switch roads could scarcely alter that. Then there was the well-known “diminishing power of the offensive”; “the active [peacetime] corps must be kept intact for the battle and not used for duties in the lines of communication area, siege-works, or the investing of fortresses,” though, at the same time, “the railways necessary to supply the army must also be guarded;24 the great cities and the populous provinces of Belgium and north-western France must be occupied”;25 such duties were a sponge soaking up fighting troops. Then there were contingencies: “should the English land and advance, the Germans will halt … defeat the English and continue the operations against the French”; no allowance of time made for that delay. Then, in a later amendment, there was the danger that the French, so despised after their collapse in 1870, might have found a new fighting will: “now that they are imbued with the offensive spirit, we must assume that the part [of their army] not attacked will advance offensively.”26 That raised the dark spectre of attrition, the long battle, to be fought out with blood and iron. The danger was there in any case: “If the enemy stands his ground in the face of the great wheeling movement, all along the line the corps will try, as in siege-warfare, to come to grips with the enemy from position to position, day and night, advancing, digging-in, advancing”; even if such advances were possible, if the Germans averted “a standstill as happened in the war in the Far East” (the Russo-Japanese War of 1904–5), the French might fall back further into the “great fortress” as which “France must be regarded”;27 “if the French give up the Oise and the Aisne and retreat behind the Marne, Seine etc.… the war will be endless.”28

  This is not the only note of desperation in the Great Memorandum. There are others. Schlieffen yearns for more troops at the decisive point, the right wing of the great wheel through Belgium and northern France: “Still greater forces must be raised … Eight army corps must be raised … We continue to boast of the density of our population, of the great manpower at our disposal; but these masses are now trained or armed to the full number of men they could yield … the eight army corps are most needed on or behind the right wing.” Schlieffen urges the creation of these eight corps, an addition of a full quarter to the strength of the army, from the reserves, the Ersatz (untrained contingents) and the Landwehr (over-age reservists), even though he apparently shared his brother generals’ fear of enlarging the army through the enlistment of unreliable elements. The note of desperation grows stronger: “How many [of the eight corps] can be transported [to the right wing] depends on the capacity of the railways … [they] are needed for the envelopment of Paris … How they advance and the attack on the position are shown on Map 3.”29

  It is at this point that a careful reader of the Great Memorandum recognises a plan falling apart: Map 3 in no way shows how the new corps are to advance or to invest Paris, the central strongpoint of the “great fortress” that was Schlieffen’s France. The corps simply appear, with no indication of how they have reached Paris and its outskirts. The “capacity of the railways” is irrelevant; railways, in Schlieffen’s plan, were to carry the attackers no further than the German frontier with Belgium and France. Thereafter it was the road network that led forward, and the plodding boots of the infantry that would measure out the speed of advance. Schlieffen himself reckoned that to be only twelve miles a day. In the crisis of August and September 1914, German, French and British units would all exceed that, sometimes day after day—the 1st Battalion the Gloucestershire Regiment averaged sixteen and a half miles during the great retreat from Mons to the Marne, 24 August–5 September, and covered twenty-three and twenty-one miles on 27 and 28 August respectively—but Schlieffen’s mean was not far short of the mark.30 Von Kluck’s army on the outer wing of the great wheel achieved a little over thirteen miles a day between 18 August and 5 September, 1914, over a distance of 260 miles.31 For the “eight new corps,” needed by Schlieffen as his plan’s clinching device, to arrive at the decisive place of action, they would have actually needed to march not only farther and faster, which defied probabilities, but to do so along the same roads as those occupied by the corps already existing, a simple impossibility.

  It is not surprising, therefore, to find buried in the text of the Great Memorandum its author’s admission that “we are too weak” to bring the plan to a conclusion and, in a later amendment, “on such an extended line we shall still need greater forces than we have so far estimated.”32 He had run into a logical impasse. Railways would position the troops for his great wheel; the Belgian and French roads would allow them to reach the outskirts of Paris in the sixth week from mobilisation day; but they would not arrive in the strength necessary to win a decisive battle unless they were accompanied by eight corps—200,000 men—for which there was no room. His plan for a lightning victory was flawed at its heart.

  It was pigeonholed for use nonetheless. Moltke the Younger, nephew of the victor of 1866 and 1870, tinkered with it when he succeeded as Chief of the Great General Staff in 1906. Schlieffen did so himself, literally up to the eve of his death on 4 January 1913. Neither solved the inherent difficulties. Moltke is conventionally accused of compounding them, by strengthening the left wing of the planned German deployment at the expense proportionately of Schlieffen’s massive right; that is scarcely the point. Moltke’s staff certainly abbreviated the time needed to entrain and offload the troops at the
frontier deployment points, by at least two days in some sectors and four in others.33 That was scarcely the point either; beyond the railways, where movement could be accelerated by planning, lay the roads, where it could not. There the inflexible average of the twelve marched miles a day cramped the calculations of the finest minds. Moltke and the Great General Staff responded to the difficulty by ignoring it. The Schlieffen Plan was left to lie in its pigeonhole, to be extracted and instituted in August 1914 with calamitous results.

  Yet the French war plan that lay in its pigeonhole in 1914, Plan XVII, proposed exactly that “favour” to Germany Schlieffen had discounted France making. It was a plan for a headlong attack across the common Franco-German frontier, into Lorraine and towards the Rhine, judged by Schlieffen the least well to serve French interests. For just as France had spent time and vast quantities of money since the 1880s in improving and extending the fortifications that protected its territory, so had Germany. The provinces of Alsace and Lorraine, annexed to the new German Empire in 1871, had been heavily fortified by France in the two preceding centuries. Under German imperial government—Alsace-Lorraine was “Reich” territory, coming directly under the administration of Berlin—the fortifications of Metz and Thionville on the River Moselle and of Strasbourg on the Rhine had been expensively modernised. Those cities were the gateways from France to Germany. Schlieffen presumed that the French high command would shrink from planning to attack them.