Thinking the Causes of World War I

John Keiger is a Professor and the Director of Research in the Department of Politics And International Studies, University of Cambridge. A different version of this article appeared as “The War Explained: 1914 to the Present” in John Horne (ed) A Companion to World War I (2010).


One hundred years since its outbreak, the causes of World War I continue to be a thriving industry, having generated by 1991 alone some 25,000 books and articles. One might expect the origins of a war that killed nine million men and injured and maimed 30 million, or that destroyed four empires and created a host of new states, to warrant explanation and even disagreement. But the origins of World War II, though more destructive, have never provoked such controversy. Today, whole books are written about how the causes of World War I have been written about.

A century after the outbreak of the Great War, it is worth reflecting on the context of some of the “causality” literature and the enduring nature of the origins/responsibility debate by looking, first, at why it is one of the most written about subjects in modern history and, second, examining the how question of the methodological approaches used to assess the causes.

Why such interest in the causes?

The war that began on August 4th, 1914 carried the germ of controversy before it even broke out. Before Britain declared war on the German Empire, Berlin rushed into print their White Book of diplomatic documents on the war’s causes, revealingly titled: How Russia and Her Ruler Betrayed Germany’s Confidence and Thereby Made the European War. The day after war began, Britain responded with its Blue Book putting its case, followed by the Russians in September, the Belgian Grey Book in October, and the French Yellow Book at the end of November 1914 entitled How Germany Forced the War. By the summer of 1915, the Austrian Red Book served up Vienna’s version of the war’s causes. Of course, resorting to “colored books“ was nothing new to international relations. But this war of self-justificatory diplomatic documentary ‘evidence,’ with its skillful selection, expurgation and elision of texts, was on a grander scale than ever before.

Prolongation of the physical war and the war of words went hand in hand. All sides invoked the “verdict of history” to apportion blame to the war’s “guilty authors.” Intellectuals, writers, journalists, and professors put their heads above the parapet to defend their nation’s innocence and their enemy’s guilt. From the most famous German professors to French philosophers of the stature of Henri Bergson—all of them battled in terms of ‘culture versus barbarism.’ This was further instrumentalized by the wartime development of modern professional government propaganda machines to shape opinion and justify the enormous sacrifices from soldier and civilian. The ideals for which each nation claimed to be fighting quickly merged with explanations of the war’s causes: “self-defense” implied the aggression of the Other, and aggression meant responsibility. But the short term question of who dunnit could never be enough; the more fundamental question of why followed naturally, and with it a Pandora’s box of explanations that ranged from the concept of the sovereign state, to nationalism, militarism, imperialism, honor, masculinity, and so on.

If the stakes in the causes of World War I were high from its outbreak—linked as they were to national honor, national sacrifice and ultimately victory—they were to be raised still further at the war’s end. It is true of many wars that nations seek to justify their participation and apportion responsibility for the outbreak, but the Treaty of Versailles, which ended the war, took the unprecedented step of including Article 231, which lay sole responsibility for the outbreak of the war with Germany and her allies—the so-called “war guilt clause.” This clause became the justification for the massive war reparations Germany was to pay in the post-war period, principally to France. It followed that if Germany could show that it was not solely to blame for the war, it could challenge the validity of Article 231, and with it the payment of reparations. This it set out to do.

The other power with an acute interest in the war guilt debate was the new Soviet regime, established following the Russian Revolution of 1917. It wished to heap discredit on its Tsarist predecessor for ideological reasons, in order to bolster its own legitimacy and popularity, both internally and externally. If it could show that the autocratic Tsarist regime, in collaboration with the bourgeois President of France, Raymond Poincaré, were together responsible through the Franco-Russian alliance for the outbreak of the Great War, the Soviets could kill two birds with one stone: discredit Tsarist Russia and partly justify not repaying to France the massive pre-war loans.

The pragmatic Soviet approach found ideological support in Lenin’s interpretation of World War I in his 1916 pamphlet Imperialism, the Highest Stage of Capitalism, which resonated with many on the European Left. His description of war as the natural consequence of the Great Powers’ competition for colonies and investment markets logically implied that the Central Powers were not alone in shouldering responsibility for the war.

In many other countries, even on the victors’ side, the notion of shared responsibility developed—largely inspired by American President Woodrow Wilson’s contention that everyone was a victim of the international system and its secret treaties. This was music to Germany’s ears, and a fillip for the revisionists. As the British wartime leader David Lloyd George later put it: “the nations slithered over the brink into the boiling cauldron of war.” In 1919, the American Senate refused to ratify the Versailles Treaty and the U.S. slipped back into isolationism with murmurs of all the powers being somehow at fault. The ground for revisionism was prepared.

The stakes in the Kriegsschuldfrage, or war guilt question, were extremely high. France made a most credible scapegoat on to whom the blame could be shifted—given the loss of the provinces of Alsace-Lorraine to Germany in 1871 and the fact that France’s effective leader in the two years preceding the war, Raymond Poincaré, had followed resolute policies intent on strengthening France’s links with her allies, especially Russia, and was a Lorrainer to boot. It was suggested that Poincaré had plotted a war of revanche against Germany to retrieve the lost provinces. The war guilt debate became all the more impassioned for the fact that in the post-war period Poincaré was still in power and pursuing a strict application of the Versailles Treaty and the payment of reparations.

Germany began a campaign to undermine Article 231. A special office was created in the German Foreign Ministry to deal with this issue—the War Guilt Section. It organized, financed and directed two other units: the Working Committee of German Associations for Combating Lies Concerning War Responsibility, which provided the ‘right’ literature and information to organizations like trade unions and various clubs; its stable-mate was the Center for the Study of the Causes of the War, created in 1921—and which from 1923 published the influential monthly journal Die Kriegsschuldfrage, edited by historian Alfred von Wegerer. This is where the ‘serious’ historical work was done to demonstrate the inaccuracy of Article 231 by “sponsoring” journalists, editors, publicists and academics in the “cause of patriotic self-censorship.” The work of these units provided much of the impetus for the ‘revisionist school,’ which in the 1920s dominated historical writing on the war’s origins from Europe to the U.S., successfully displacing much of the blame from Germany.

Paradoxically, Germany’s campaign found support in French domestic politics. The Left, notably the newly formed French Communist Party, wished to stop Poincaré returning to power by tarring him with responsibility for the war and depicting him as “Poincaré-la-guerre.” This was fertile ground for German and Soviet propaganda. Layer upon layer of myth and counter-myth, truth and lies, clouded and troubled even serious historical debate. Unlike the outbreak of World War II, where cause and responsibility were clearer and less contested, the history of the origins of the Great War went through cycles of revisionism and post-revisionism. Viewed as a trend over the hundred years since its outbreak, it could be argued that responsibility for the conflict has never stayed firmly fixed and no single country has been squarely and permanently nailed, even if the consensus has been that Germany bore primary responsibility for its outbreak—an interpretation recently referred to as “the German paradigm.”

The question of national interest aside, the war’s causes have generated study for less political reasons. The war’s sheer scale, destructive power and consequences have continued to disorientate and mesmerize the intellectual community, which has sought deeper and grander explanations to match the war’s scale. The American diplomat and historian George Kennan declared in 1979 that World War I was “the great seminal catastrophe of this century.” A catastrophe, then, whose causes needed to be explained, as a duty to humanity, in order to comprehend the war’s momentous consequences: communism, fascism, the Gulag, the Holocaust, World War II and, as the well-known British historian Eric Hobsbawm put it in his Age of Extremes (1994), one of the worst centuries in the history of humanity only brought to a close by the coming down of the Iron Curtain in 1989.

A further explanation to do with historical evidence has also continued to fan the flames of debate and to explain why for all the historical research carried out in the last hundred years, a strong whiff of doubt continues to surround the causes of the war. Historically, there are still areas associated with the immediate causes of the conflict where the archival evidence remains incomplete on important issues, such as the details of the discussions between the Tsar and French President Raymond Poincaré during the latter’s visit to Russia (France’s ally before the war) in July 1914.

Then there is the explanation that the war’s causes have found favor with policymakers as a counter-model. The outbreak of World War I has become an object lesson in how not to conduct international politics: an example of poor “crisis management.” During the 1962 Cuban Missile Crisis, when the world apparently stood on the brink of World War III between the two nuclear superpowers, American President John F. Kennedy, possessing no textbook of crisis-management for presidents, ordered his close decision-making circle to read Barbara Tuchman’s 1962 book The Guns of August —which detailed the frenzied and confused international decision-making process that ended in the outbreak of the Great War—so as not to repeat the error. Kennedy’s intention in particular was to ensure that the process of decision-making did not run away with itself in the way it seemed to do in 1914, and to ensure that the lines of communication were maintained with the Soviet leadership.

Before Cuba, there was little by way of an explicit theory of crisis management to guide policymakers in international relations. Since then, July 1914 has become a key example in the handbooks of management techniques for decisionmakers. The unfolding of the July Crisis is now analyzed in terms of information processing, decision-making under crisis, command and control, the coordination of diplomatic and military actions, and the problems of communication with an opponent.

Evolving methodologies have also stimulated and prolonged interest in the causes debate. Analysis has moved a long way from the narrowly defined ‘diplomatic history’ accounts of the international relations of 1914 focused, in the time-worn phrase, on “what one Foreign Office clerk wrote to another.” Today, international historians borrow from a range of disciplines to understand the intricate web of causality from international relations theory, political science, and security studies, to economics, sociology, anthropology, and so on. In broad methodological terms, it might be said that how the causes of the war are studied falls into two approaches: structuralist and intentionalist causes.

How do we study the causes?

From a methodological point of view, most causality in history involves separating impersonal from personal actions, and assessing their relative weight. Social scientists call this the difference between structural or functional explanations of causality (economic, social, political or imperial) and intentionalist (individual decisions) explanations. In the Great War’s causality, structural (or big causes) and intentionalist (or individuals’ roles) have vied with each other for primacy. As the British historian James Joll noted: “We often feel that the reasons the politicians themselves were giving are somehow inadequate to explain what was happening and we are tempted to look for some deeper and more general cause to explain the catastrophe.” And Joll quoted the great Italian authority on the war’s origins, Luigi Albertini, who referred to “the disproportion between the intellectual and moral endowments [of the decision makers of 1914] and the gravity of the problems which faced them, between their acts and the results thereof.”

This goes to the heart of the debate about human agency and structural causes in historical causality. When the German Chancellor, Bethmann Hollweg, remarked on the eve of war on July 30th, 1914 that the people were peaceful “but things are out of control,” does this imply that individuals could do nothing and that somehow greater forces had taken over? Or could it be that individual decision-makers can sometimes be overwhelmed by events, not because of greater forces bearing down on them, but for perfectly understandable short-term reasons—speed of events, lack of communication, error, misinterpretation, and incompetence (all of which President Kennedy sought to avoid in the 1962 Cuban Missile Crisis). Thus the actions of politicians and the military can be a good deal less rational than conspiracy theorists might have us believe. But absence of rationality does not mean that historians should immediately reach for structural explanations; human error, incompetence or losing control of events are legitimate causes in their own right, as the recent book with the telltale title The Sleepwalkers: How Europe Went to War in 1914 (2013) by Cambridge historian Christopher Clark has suggested.

Nationalism, militarism, Social Darwinism, public opinion, domestic causes, imperialism, the alliance systems—to name the most prominent structural causes—have at one time or another jostled for prominence against the activities of individual decision-makers, and James Joll’s Origins of the First World War (1984) provides a balanced analysis of structural versus individual causes. But what is the nature of these structural causes? While it is not possible within the constraints of this article to outline all of them, it is important to get a flavor of their nature in order to understand the wider debate on the causes of World War I.

Nationalism’s role in causality is usually presented as no longer the positive and liberating nationalism that was said to characterize the French revolutionary armies, but the subsequent militaristic nationalism that asserted nationhood through conquest. This had a powerful effect when combined with philosophers identifying war as positive, such as Friedrich Nietzsche, or modelling the development of society on the discoveries of Charles Darwin’s 1859 Origin of Species, with its notions of natural selection and survival of the fittest. Thus many believed that societies and peoples behaved according to the same biological laws as animals and plants, and that they survived or died out according to strength and fitness for purpose. The resulting Social Darwinism was, it is argued, powerful and pernicious, and drove elites towards war as the final test of fitness.

By the end of the nineteenth century, the purely historical concept of the Nation began to be fused with the pseudo-biological concept of race, to imply a supposed superiority of certain races and a legitimization of the conquest of inferior ones. War then could be seen as a positive test of the survival of the fittest, as well as a justification for the expansion of armies and the development of a military posture. These underlying trends in European society, it is argued, played a role in the complex matrix of causality.

These abstract theories entered the collective consciousness through the development of national education systems in Europe after 1870, when an increasing number of states adopted free compulsory schooling. In France, it was said to have been the Prussian schoolmaster who had won the 1870 Franco-Prussian War; Britain’s victories, it was claimed, were won on the playing fields of Eton. Increasingly, there were fewer and fewer limits on what the nation could ask of its citizens. The schools of the French Republic, Britain, Germany, Austria-Hungary, Italy all cultivated notions of duty and honor, and of serving one’s country right down to the supreme sacrifice, so sardonically undermined by the war poet Wilfred Owen in his “Dulce et decorum est.”

The militarization of European societies, another structuralist cause, continued apace in peace-time through compulsory military service on the European continent, where insidious propaganda reinforced notions of the glory and superiority of one’s own nation. This was instrumentalized in civil society by the popularity of military bands and tattoos, the romanticism of the soldier, rifle clubs, and para-military organizations, such as the Boy Scout movement, founded by Lt Col Baden-Powell, hero of the Battle of Mafeking, for which the uniform was an exact imitation of Baden-Powell’s own in Kashmir in 1907, and whose motto ‘Be Prepared,’ had originally been followed by ‘to Die For Your Country.’ By this process, armed forces became the incarnation of the nation.

At the same time, the steady democratization of European societies resulting from the extension of the suffrage, participation in state machinery from local government to the payment of taxes, the development of a mass culture through a popular press—with newspapers such as Britain’s Daily Mail reaching an audience of one million readers by 1896—meant that citizens increasingly identified with the State, which filled the vacuum left by the decline of Religion and the Church. Citizens drew direct and tangible benefit from the State—for example through old age pensions in Germany and Britain in the 1890s and 1909, respectively. Many now had an interest and a stake in the State and were increasingly willing to defend it, even to the death. As a consequence, war was no longer the sole prerogative of kings or even political leaders, but was increasingly the focus of the people—and not just the middle classes.

The music halls made ‘jingoism’ a source of fun and entertainment for the “man on the Clapham omnibus.” His political support could be conjured up for the expansion of armaments programs, as with the popular cry of “We Want Eight and We Won’t Wait,” which called for the laying down of more British Dreadnought battleships in 1909 to counter the German naval expansion program.

Of course, even the structuralists would not claim that this made war inevitable, but they would suggest that it helped make the mobilization of the masses easier when a crisis or a conflict came. Public opinion, they would argue, could always be called upon to uphold the values and principles of the Nation. Hence, in 1914 when war came, all sides, the British, French and Russians on the one hand, or the Germans and Austro-Hungarians on the other, could claim that they were fighting a just war—a defensive war for the values of their nation which, after all, was superior to those of others.

Thus, by 1914 war was more than ever a question of life or death, not just for individual citizens, but for states themselves, who believed that if at this moment they did not stand up to their opponents they would disintegrate, become prey to revolution or, at best, have to live in the shadow of their rivals.

Such reasoning had long been a stimulant for increased military spending, the development of an arms race, and an offensive posture and strategy—with a direct impact on those who were paid to defend the nation, namely the military. They increasingly called for the nation to be prepared for any security threat from abroad. This, in conjunction with the underlying trend of technological developments in the nature of armaments (better guns, ships, and equipment), led to greater emphasis being placed on possessing a margin of superiority over one’s potential enemy. This, in turn, meant knowing one’s enemy—reflected in the development at the beginning of the twentieth century of modern intelligence agencies seeking to secure that additional information about their potential enemy’s strategy, tactics, and equipment that might give them a margin of superiority in any conflict. This contributed to the European arms race, which is also in the opinion of some an underlying or structural cause in the outbreak of war in 1914—the major powers’ total expenditure on defense rising by more than 50 percent in the years 1894 to 1896 alone. The strategic invasion plans of the major powers, from the German Schlieffen Plan to France’s Plan XVII, with their emphasis on speed of mobilization and tight logistics, heightened an already febrile international atmosphere with trigger-happy military commands—War by Timetable, as the English historian A.J.P. Taylor called it.

One of the oldest structural causes is that of economic rivalry, first made famous by Karl Marx, who claimed that “wars are inherent in the nature of capitalism: they will only cease when the capitalist economy is abolished.” Certainly economic rivalry between states from the 1890s, epitomized in books such as Made in Germany or Le danger allemand (both published in 1896), in which Germany was depicted as stealing British or French markets, was a further source of tension in international relations up to 1914. Also to blame, according to Lenin, was capitalism’s offspring, imperialism. In his 1916 pamphlet Imperialism, the Highest Stage of Capitalism, Lenin argued that since the turn of the twentieth century, capitalism had entered an even more aggressive phase that placed a premium on new investment opportunities that could only be developed through the control of new colonies and markets, leading to imperial rivalry between the powers.

However, though both economic and imperial rivalries did exist, it should not be overlooked that there was also much economic and imperial cooperation between major powers prior to the war. In similar vein, some analyses have promoted the idea that in order to contain, overcome, or defuse social unrest or revolution at home, elites sought external war as a means of overcoming or defusing potentially dangerous domestic political situations.

A large and broad structural explanation, boosted of late by political scientists and international relations theorists, has focused on the international system per se.

Systemic explanations focusing on causality arising from the workings of the international system have a long history. As early as the 1920s, British classicist G. Lowes Dickinson famously described the prevailing state of international relations in 1914 as one of “international anarchy.” The end of peace has also been explained in terms of the gradual erosion of the old Concert of Europe, whereby the Great Powers from the end of the Napoleonic Wars regularly, albeit informally, concerted on problems or adjustments that needed to be made to the international system. Other systemic explanations have found favor with interdisciplinary historians working on the margins of international relations theory, such as Sir Harry Hinsley, who suggested that every general war since 1494 occurred when the international system was undergoing a massive shift in the sources and distribution of international power, no general wars have occurred outside these shifts in power. Thus, World War I resulted from an “international unsettlement” which began in the 1890s, in part characterized by the rise of Germany.

Other system analysts, such as Paul Schroeder, have suggested that instead of focusing on the causes of war, scholars should analyze the causes of peace and why that peace no longer held. After all, 1914 was the first time that the European Great Powers had been at war with each other for 40 years—and that it was the first conflict involving all the Great Powers in a century. Why should it be that between 1815 and 1914, twenty-three international wars had been fought on the European continent—of which half had been small wars involving fewer than 10,000 battle fatalities—and that those conflicts had not led to a general conflagration of the Great Powers, even though World War I began as a local war launched by Austria-Hungary against Serbia.
Schroeder believes that the breakdown of peace requires a deeper understanding of what ‘realists’ in international relations theory would study, such as the nature of the international system, its political culture, norms, rules and practices, the existing distribution of power, the constituent
states’ opportunities for maneuver, their vulnerabilities, and the power-political patterns of behavior.

Perhaps less attention should be given to the states in the system whom we now know to have been at greater fault in the war’s cause—the Central Powers of Austria-Hungary and Germany—and more attention to the dominant powers— namely France and Britain—whose system it largely was, and who regulated it unofficially through the remnants of the Concert of Europe, and who held the initiative in world affairs in what was a zero-sum game. In other words, should more research be devoted to how the system was made fragile and unstable by the tension between ‘satisfied’ and ‘unsatisfied’ powers?

Reflecting the way that historians write about the present when thinking about the past, models of the war’s causality have often reflected contemporary international relations. During the Cold War and the division of the world into two blocs, there was a tendency also to view the pre-World War I era as bipolar and divided between two rigidly separated and rival blocs of Triple Alliance and Triple Entente (thereby ignoring the numerous examples of Great Power détente prior to 1914). This crystallization of the two blocs became a causal explanation in which power, prestige and security were key determinants in the war’s outbreak. As British historian David Stevenson has pointed out, during the resurgence of superpower tension under U.S. presidents Carter and Reagan in the late 1970s and early 1980s, American political scientists and historians analyzed the pre-1914 system in terms of comparative and thematic studies of war plans, intelligence and armaments. This analysis turned on how far war was accidental or system-generated, and how far it was willed by governments.

It could be argued that in the post-Cold War era, traditional ideological international politics have given way to ethnic nationalism, the primacy of economics, and greater reference to cultural determinants of power politics in the vein of Francis Fukuyama’s End of History (1992) or Samuel Huntington’s Clash of Civilizations (1996), and that this has influenced writing on the causes of World War I today. Thus, more ethno-cultural explanations of the Great War’s outbreak have come to light in the post-Cold War world. Avner Offer has underlined the importance of codes of honor and duty—right down to the supreme sacrifice—among the European elites as helping to explain the inflexibility of certain leaders and their inability to back down for fear of dishonoring themselves and their country. Thomas Lindemann has placed the emphasis on the ethno-cultural role of Social Darwinism in influencing German decision-makers and their perception of international relations. With the ‘New World Disorder’ of the opening decades of the second millennium, one might expect historians to begin thinking anew along the lines of Lowes Dickinson’s “international anarchy” to explain the origins/causes of World War I.

And so the sedimentation of underlying or structural causes can go on being built up until the accumulated strata point to only one conclusion: the inevitability of the war. But such determinism still begs the question as to why the war occurred in 1914 and not before or after. In the end, it is not a structural cause that pulls the trigger.

Thus some historians have preferred the intentionalist approach, focusing on the immediate short term actions of individual decision-makers and the immediate reasons why they took those decisions in 1914. They have tended to believe that these intentionalist explanations are the only ones that can be supported by documentary evidence, and that to reason in terms of structural causes is to impose a pattern on events that cannot be demonstrated on the basis of hard evidence. Nevertheless, much of the intentionalist school has taken on board James Joll’s pioneering work from the late 1960s on the “unspoken assumptions” that underly the thought processes of the decision-makers, as well as their limited freedom to choose in particular circumstances.

Most would accept that individual decision-makers and governments were conditioned in their reasoning and perceptions of events by broader societal trends resulting from longer cultural, political, social or educational traditions, and that consequently their freedom to choose was limited.

The tension between structural and intentionalist causes was incisively analyzed in 2003, in a collection edited by historian Holger Herwig and sociologist Richard Hamilton, who criticized the highly deterministic processes that underly structural causes and the way in which, according to them, they always yield a given outcome whatever the nature or activity of the decision-makers. They also criticize the highly selective way that certain structural explanations are highlighted while others are ignored; at fault can be the choices scholars themselves make! Thus, nationalism predominates over the forces of internationalism, militarism over pacifism, alliance systems are blamed even though the contents of many of the secret treaties were not known at the time, or public opinion is summoned up when little is known about what mass attitudes represented given the absence of opinion polling, while the press is analyzed without any explanation of readers’ reactions to it. Hamilton and Herwig come down on the side of the intentionalists, and call for greater research into the mindsets and actions of what they refer to as the “coterie of elites” among the decision-makers.

While one would not disagree with that call for more research, it is to be hoped that in future the either/or accounts—even antagonism between the two—could be replaced by a more integrated analysis that brings together long-term and immediate causes so that a clearer picture of causality emerges from the given conditions with which governments necessarily live at various moments, and the actions that they and individual decision-makers take.

Historians & Decision-makers

There is no sign of interest in the causes of World War I abating—quite the contrary, given the centenary. One cannot fail to notice the deluge of new books on the war, some already best-sellers (e.g. Clark’s Sleepwalkers, with 300,000 copies sold, of which 160,000 in Germany by 2014)—not to mention the media coverage. The war’s causes have been analyzed dispassionately by some outstanding scholars and historians, but also politically and polemically, from varied standpoints and with different objectives in mind. One hundred years on, are we any closer to a consensus on the causes?

If the current crop of academic books and articles on the subject is anything to go by, it would seem not. Some continue to insist on Germany’s primary responsibility, others nuance or even contest it. Perhaps that is in the nature of historical enquiry into the causes of great events. But it is worth reminding ourselves of French historian Marc Bloch’s words of caution on causality in history:

A graduated classification of causes, which is really only an intellectual convenience, cannot safely be elevated to an absolute. Reality offers us a nearly infinite number of lines of force which all converge together upon the same phenomenon. The choice we make among them may well be founded upon characteristics which, in practice, fully merit our attention; but it is always a choice.

So, scholars too make choices, just like the men of 1914. Heaven forefend that they should ever miscalculate. Historians would do well to reflect on that from time to time when judging the decision-makers of 1914.

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