The causes of World War I remain contested a century after the war itself concluded. Some authors emphasize the accidental character of the war as an unplanned response to the assassination of Archduke Francis Ferdinand, the heir to the Austro-Hungarian throne, in June 1914. Others argue that the German General Staff planned the war in advance and used the assassination as a pretext. Military officers of this time were taught a doctrine called "cult of the offensive." This doctrine instructed commanders to take advantage of any opportunity to launch an offensive. Although the doctrine was embraced by military forces in various countries, the role played by war planners in German policymaking was especially notable.
Until 1904, the German war planners focused on defensive responses to a possible Russian attack. When Europeans thought about war, it was more likely to be an Anglo-Russian war than one that involved Germany. Germany's shift to an offensive strategy can be traced to Russia's defeat at the hands the Japanese in 1905.
To take advantage of Russia's vulnerablity during the war with Japan, Chief of Staff Alfred von Schlieffen developed a plan to invade France by way of Belgium. During the First Morroccan Crisis of 1906, Kaiser Wilhelm II found that German public opinion and the army's lack of up-to-date artillery did not allow him to implement a plan of this type. To remedy the situation, recoiless artillery was introduced, naval buildup was accelerated, and propaganda was distributed through the Navy League that accused Britain of "encircling" Germany and denying the country its rightful "place in the sun," meaning a share of colonies.
The effort to influence German public opinion met with limited success until the Agadir Crisis of 1911. In this incident, France and Britain combined to oppose German colonial ambitions in Africa. Germany did not have the resources to outbuild a combined Anglo-French fleet, so a new strategy had to be developed. The Reichstag approved army expansion, required to implement the Schlieffen Plan, in July 1913. The logic of the cult of the offensive doctrine meant that this vote would be treated as a mandate for war. The kaiser suggested that an offensive that focused on Russia alone might avoid unnecessary war with France and Britain. Chief of Staff Helmuth von Moltke objected that the army had no choice but to follow the Schlieffen Plan, which by this time represented a longstanding consensus on the General Staff.
During the war, the German government blamed Russia for the outbreak of hostilities. This view was undermined when telegrams between Kaiser Wilhelm I of Germany and Tsar Nicholas II of Russia were discovered in the Russian archive and published in 1920. They show Nicholas making various peace proposals and Wilhelm brushing them aside.
Much of the debate on the war's causes was inspired by the "war guilt" clause of the Treaty of Versailles, which was used to justify reparations. The view that Germany was no more guilty than other nations was orthodox from the 1920s until the 1960s. The classic work of this type is the popular and highly readable Guns of August (1962) by Barbara Tuchman. Tuchman's book was published around the time of the Cuban missile crisis and became well known due to contemporary comparisons.
Fritz Fischer's Germany's Aims in the First World War (1968) argues that Germany was committed to war at least as early as July 1913, when the Reichstag approved unsustainable emergency spending for army expansion. This was a full year before Franz Ferdinand's assassination. Fischer supports his argument with material from a diplomatic archive that was collected privately by Karl Kautsky. The Kautsky documents include incriminating material that was left out of the official archival set.
At the end of the Cold War, historians gained access to significant new material from the German military archive in Potsdam. Annika Mombauer presents this material in Helmuth von Moltke and the Origin of the First World War (2005).
Fischer's views were updated for the 21st century by David Fromkin in Europe's Last Summer: Who Started the Great War in 1914? (2004). Meanwhile, Christopher Clark's The Sleepwalkers: How Europe Went to War in 1914 (2014) argues that it is pointless to blame any single nation for the war.
Numerous authors have written on the subject of the causes of the war and they have cited a wide variety of causes. These include nationalism, militarism, imperialism and a web of pre-war of diplomatic agreements, many of them not disclosed until after the war.
The notable historians of this period can be divided into two camps. One camp sees the war as arising from the assassination of the Austro-Hungarian heir in June 1914 and snowballing almost spontaneously due to the alliance structure and military plans that were in place. This view throws the blame widely and avoids blaming Germany or any other party too specifically.
Another camp sees the war as a consequence of Germany's military planning and foreign policy, which became increasingly aggressive in the years leading up to the war. This view originated with the writings of German historian Fritz Fischer in the 1960s and has been referred to as the "Fischer thesis." The General Staff focused on offensive concepts, including the Schlieffen plan to invade France, which was drawn up in 1904.
From 1902 to 1911, a "naval race" between Germany and Britain was a focus of patriotic pride in both countries. The navy was popular with the German public, who thought of it as a way for their country to gain a larger share of colonies. Policymakers generally dismissed colonial ambitions and thought of the navy as a tool to be used in European politics. After Britain and France stood together in the Agadir Crisis in 1911, German leaders shifted their focus to the army. Germany did not have the resources to outbuild a combined Anglo-French fleet.
The war began in 1914 between two coalitions. The "Central Powers" comprised the German and Austro-Hungarian Empires, later joined by the Turkish (Ottoman) Empire. The "Allies" included the British, Russian and French Empires, Japan, and Serbia. The powers had vast overseas empires in Asia, Africa and the Western Hemisphere (including Canada) that were active participants.
Nationalism and ethnic tensions between Germans and Slavs were the basic reasons that the war was fought. Religious affiliations (Catholic, Protestant, Eastern Orthodox, Muslim) overlapped language to produce closed ethnic communities which were highly motivated to fight their traditional enemies. Typically, each ethnic group dominated a central homeland, which had minorities, and also claimed a larger territory. Some claims were centuries old, others were new; they all overlapped. The incantation "it's ours because we were here first" cast a spell on otherwise peaceful peoples and guaranteed perpetual hostility.
For 800 years the Germans had been moving towards the Slavic parts of Central Europe in Europe, attempting to push out the Slavs. Wealth was based on agriculture, so possession of land was decisive. Germany had been unified from Prussia and numerous smaller countries in 1870, and rapidly built a powerful industrial economy with a strong agricultural base. Active imperialism led to the acquisition of numerous colonies in Africa and the Pacific, such as New Guinea. None of the colonies were profitable, but now Germany had a world empire. German's main rival was Britain, with a smaller home population and a much larger empire, well protected by the world's strongest navy. By 1914 under the leadership of Admiral Alfred von Tirpitz, Germany had a good fleet, but the Royal Navy remained well ahead in sea power. The naval race heightened rivalries between the two powers, but did not itself cause the war.
After 1900 the Slavs—led by huge Russia and little Serbia—were fighting back. Militant Pan-Slavic ideology demanded that oppressive German, Hungarian and Ottoman rule be overthrown, so that the Slavs could have their own nation states. Trouble flared in the Balkans, where two recent wars had revealed a propensity to use violence as a first remedy. Belgrade (the capital of Serbia) promoted unrest among Serbs in nearby Bosnia-Herzegovina, a multi-ethnic region that the Austro-Hungarian Empire had recently taken from Turkey and now planned to incorporate. The imperial capital, Vienna, was increasingly nervous that unrest among the various minority groups would lead to the breakup of its empire. The only way to keep control was to aggressively suppress nationalist uprisings and stop outsiders from inciting rebellion. On June 28, 1914, Archduke Ferdinand, heir to the throne, visited Bosnia to legitimize his Empire's claim to that province and upgrade its status. In Sarajevo a team of Bosnian Serbs assassinated him and his wife.
Alliances and Escalation
The Austrian Empire's response escalated the conflict. The escalation was facilitated by the alliance network the major countries had built. Austria was closely allied to Germany and Italy through the "Triple Alliance" of 1882. Turkey was close to Germany and hostile to Russia. Russia and France were allied since 1894. Russia, acting without French approval, played the role of protector of the smaller Slavic nations, especially Serbia.
Britain remained aloof from the alliance system. Germany, influenced by the naval theories of the American Alfred Thayer Mahan, embarked on a campaign of naval building, which the Kaiser and his naval minister, Alfred von Tirpitz, hoped would help Germany achieve her "place in the sun" among the world powers, and perhaps force the British into an alliance through fear of German naval power. The British responded with an even bigger naval program. The German naval building campaign could not meet its goals, and the British became increasingly alienated from the Germans, whom they increasingly saw as rivals and potential European hegemons. The "Entente Cordiale" of 1904, which dealt with outstanding colonial questions between France and Britain in North Africa, was not a military alliance but it did symbolized Franco-British rapprochement. The Anglo-Russian Entente of 1907 settled outstanding conflicts of interest between Russia and Britain. As a result, there was a general alignment of France, Britain, and Russia known as the "Triple Entente."
Britain thus was officially neutral but was unwilling to accept the possibility that Germany and the Austro-Hungarian Empire would control the European continent militarily and economically. The United States refused to become involved in any way and insisted on complete neutrality.
Historian Jacques Barzun observed how Darwinism caused the horrendous brutality of the wars leading up to this one: "Since in every European country between 1870 and 1914 there was a war party demanding armaments, an individualist party demanding ruthless competition, an imperialist party demanding a free hand over backward peoples, a socialist party demanding the conquest of power and a racialist party demanding internal purges against aliens — all of them, when appeals to greed and glory failed, invoked Spencer and Darwin, which was to say science incarnate." For more information, please see: World War I and Darwinism
The July 1914 Crisis and Declarations of War
On June 28, 1914, Archduke Franz Ferdinand was assassinated while visiting the city of Sarajevo by a team of trained assassins sent by The Black Hand, a pan-Slavic group financed by Serbia. Following the assassination and Germany's giving of a "blank check" of support to the Austro-Hungarians, a series of demands were issued to Serbia by Austria-Hungary with a strict 48-hour deadline. While the Serbian government offered to meet many of the demands, Prime Minister Nikola Pasic refused to turn over three men identified by Austrian authorities as being behind the attacks, declaring that to do so "would be a violation of Serbia's Constitution and criminal in law." Three days later, the Austro-Hungarian Empire declared war on Serbia.
Preparation for War
Convinced that now was the time for a showdown, Austria issued an ultimatum to Serbia. Germany supported Austria. Russia announced support for Serbia, and France supported its ally Russia. Each nation in Europe (except Britain) had long trained most or all its young men in the army for two or three years, then retained them for long periods in reserves. That meant each country had a small professional army, and a very large reserve army that could be mobilized in a few days. Russia mobilized on July 28, followed in a matter of days or even hours by its rivals and allies. The Central powers had about 7.5 million regulars and reservists; Germany had 4.5 million, Austria 3.0 million; (in addition they were joined by Turkey with 2.9 million and Bulgaria with 1.2 million.) The Allies had larger numbers, Russia 6.0 million; France 4.0 million; Britain and Empire, 1.0 million; and Serbia 200 thousand, for a total of 11.0 million at the start. Later the Allies were joined by Italy (5.6 million), and the United States (4.4 million), as well as smaller countries. In the course of the war 1914-1917 the Central powers used 23 million different soldiers and the Allies 43 million. In 1914 the long-term numbers did not matter—it only mattered how many combat soldiers could be sent in a few days to defend the border, or better, to invade the neighbor. The Germans, with better organization and better railroads, made the most effective use of their manpower, while the dinosauer-like Russian Empire ran far behind schedule.
Few leaders seem to have feared war in 1914—indeed, the prevailing mood was that the world had become too cultured, too dull and boring. Warfare was the challenge needed to restore "manliness" to its "natural" state of warlike being, after so many years of softening in factories and offices. War seemed better than peace—and peace itself appeared dangerous because everyone feared their enemies were growing stronger year by year. Throughout Europe the public therefore enthusiastically supported going to war—even the supposedly antiwar Socialists went along. All the nations wanted to win, and their generals told them the way to win was take the offensive. The logic comprised two parts: First, armies were more mobile because of elaborate railroad networks, telegraph systems and highly detailed mobilization plans. Second, firepower was much greater because of the vastly bigger armies and because the new industrial technology had created better offensive weapons, especially artillery, against which no one had developed defenses. Therefore, the offense could whip the defense, and the first to attack would win. The last great war, between France and Germany in 1870-71 had been decided in a matter of weeks. No one looked back to the drawn-out American Civil War, as a warning.
- Bakeless, John Edwin. The Economic Causes of Modern War: A Study of the Period: 1878-1918 (1919) online edition
- Clements, Kendrick A. "Woodrow Wilson and World War I," Presidential Studies Quarterly 34:1 (2004). pp 62+. online edition; excerpt online
- Cramer, Kevin. "A World of Enemies: New Perspectives on German Military Culture and the Origins of the First World War," Central European History (2006), 39#2 pp 270–298 online at CJO
- Evans, R. J. W., and Hartmut Pogge Von Strandman, eds. The Coming of the First World War (1990), essays by scholars from both sides online edition
- Fay, Sidney. The Origins of the World War (1930); classic scholarly study; argues every nation shared guilt for starting the war online edition
- Fromkin, David. Europe's Last Summer: Who Started the Great War in 1914?, (2004), ISBN 0375411569.
- Gilpin, Robert. War and Change in World Politics (1981) excerpt and text search
- Hamilton, Richard F. and Holger H. Herwig, eds. The Origins of World War I, (2003) 553pp; 15 long essays by leading scholars; excerpt and text search
- Hamilton, Richard F. and Holger H. Herwig, eds. Decisions for War, 1914-1917 (2004) ' a condensed version in 282pp
- Henig, Ruth The Origins of the First World War (2002) 76pp online edition
- Hewitson, Mark. Germany and the Causes of the First World War (2004)
- Joll, James. The Origins of the First World War. (3rd ed 2006).
- Kennedy, Paul M. (ed.). The War Plans of the Great Powers, 1880-1914. (1979)
- Kennedy, Paul M. The Rise of the Anglo-German Antagonism, 1860-1914 (1981)
- Lee, Dwight E. ed. The Outbreak of the First World War: Who Was Responsible? (1958), readings from multiple points of view
- Lieber, Keir A. "The New History of World War I and What It Means for International Relations Theory." International Security (2007) 32:2, 155-191
- Link, Arthur S. Woodrow Wilson and the Progressive Era, 1910-1917 (1972) standard political history of the era
- Maier, Charles S. "Wargames: 1914-1919" in Rabb T. and Rotberg R. (eds.), The Origins and Prevention of Major Wars, (1989), 249-279
- May, Ernest R. The World War and American isolation, 1914-1917 (1959) online at ACLS e-books
- Miller, Steven E. (ed.) Military Strategy and the Origins of the First World War: an International Security Reader, (1985)
- Page, Thomas Nelson. Italy and the World War (1920) online edition
- Ponting, Clive. Thirteen Days: Diplomacy and Disaster - The Countdown to the Great War (2002)
- Snyder, Jack L. The Ideology of the Offensive. Military Decision Making and the Disasters of 1914. (1984), 267 pp. excerpt and text search
- Stevenson, David. The First World War and International Politics (2005)
- Van Evera, Stephen. Causes of War. Power and the Roots of Conflict. (1998), chap.7, 193-239.
- Williamson, Samuel R. Jr. "The Origins of World War I" in Rabb T. and Rotberg R. (eds.), The Origins and Prevention of Major Wars, (1989), 225-248.
- Williamson, Samuel R. The politics of grand strategy: Britain and France prepare for war, 1904-1914 (1990) online at ACLS e-books
- Williamson Jr. Samuel R. and Ernest R. May. "An Identity of Opinion: Historians and July 1914," Journal of Modern History(2007) Volume 79, Number 2, 335-87, historiography
- Sidney Fay, The Origins of the World War (1930) classic scholarly study; argues many nations shared guilt for starting the war
- Van Evera, Stephen, "The Cult of the Offensive and Origins of the First World War," International Security, Summer 1984.
- "Germany's Reasons for War with Russia." From the World War I Document Archive at the Brigham Young University Library.
- Levine, Isaac Don, "Willy-Nicky Letters between the Kaiser and the Czar." From the World War I Document Archive at the Brigham Young University Library.
- Outbreak of the World War (1924). German documents collected by Karl Kautsky and edited by Max Montgelas and Walther Schiicking. New York: Oxford Univ. Press. The German version was published in 1919 as Die deutschen Dokumente zum Kriegsausbruch.
- Italy was originally a Central Power, but remained neutral in 1914 and joined the Allies in 1915.
- The term "Slavic" refers to languages, and by extension to the corresponding ethnic groups. The main Slavic languages were Russian, Ukrainian, Polish, Serbo-Croatian, Czech, Slovak, and Bulgarian. Note that the Albanians, Estonians, Finns, Germans, Greeks, Hungarians, Italians, Jews, Latvians, Lithuanians, Romanians and Turks who also lived in Central Europe did not consider themselves Slavic, because their languages were distinctively different.
- The assassination was planned in Serbia with the assistance of Serbian mid-level military and government officials, but not the government itself. Bosnia receded into the background in 1914, only to reappear center stage 79 years later. In 1993 the powers issued an ultimatum to Belgrade ordering it to stop helping the Bosnian Serbs, who were engaged in "ethnic cleansing" against Bosnian Muslims
- R.Ernest Dupuy and Trevor Dupuy, The Encyclopedia of Military History (1985) 990.