The causes of World War 1 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 Franz 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 of the Japanese in 1905.
To take advantage of Russia's vulnerability during the war with Japan, Chief of Staff Alfred von Schlieffen developed a plan to invade France by way of Belgium called the Schlieffen Plan.
During the First Moroccan 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, recoilless artillery was introduced, the 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.
Multiple causes
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 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.
Ethnic nationalism
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 that 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 the 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. Germany'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 hegemony.
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 symbolize 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.
Darwinism
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.
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 and 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 dinosaur-like Russian Empire ran far behind schedule.
Few leaders seemed 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 to 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 was decided in a matter of weeks. No one looked back to the drawn-out American Civil War as a warning.