Alliances as a cause of World War I

A representation of the Triple Alliance, with Italy as the junior partner

Though their significance is often misunderstood or exaggerated, alliances are one of the best-known causes of World War I. While alliances did not force nations to war in 1914, they nevertheless drew them into confrontation and conflict with their neighbours.

What is an alliance?

An alliance is a political, military or economic agreement, negotiated and signed by two or more nations. Military alliances usually contain promises that in the event of war or aggression, signatory nations will support their allies.

The terms of this support are outlined in the alliance document. They can range from financial or logistic backing, like the supply of materials or weapons, to military mobilisation and a declaration of war against the aggressor.

Alliances may also contain economic elements, such as trade agreements, investment or loans.

Origins of the alliance system

In many respects, the pre-war alliance network as a byproduct of European geopolitics. Europe had long been a melting pot of ethnic and territorial rivalries, political intrigues and paranoia.

France and England were ancient antagonists whose rivalry erupted into open warfare several times between the 14th and early 19th centuries. Relations between the French and Germans were also troubled, while France and Russia also had their differences.

Alliances provided European states with a measure of protection. They served as a means of guarding or advancing national interests while acting as a deterrent to war. They were particularly important for Europe’s smaller or less powerful states.

Anti-Napoleonic alliances

During the 1700s, kings and princes regularly formed or re-formed alliances, usually to protect their interests or to isolate rivals. Many of these alliances and alliance blocs were short-lived. Some collapsed when new leaders emerged; others were nullified or replaced by new alliances.

The rise of French dictator Napoleon Bonaparte in the early 1800s ushered in a brief period of ‘super alliances’. European nations allied themselves either in support of Bonaparte or to defeat him. Between 1797 and 1815, European leaders formed seven anti-Napoleonic coalitions. At various times these coalitions included Britain, Russia, Holland, Austria, Prussia, Sweden, Spain and Portugal.

After Napoleon’s defeat at Waterloo in 1815, European leaders worked to restore normality and stability to the continent. The Congress of Vienna (1815) established an informal system of diplomacy, defined national boundaries and sought to prevent wars and revolutions. The congress system worked for a time but started to weaken in the mid-1800s.

The late 19th century

Imperial interests, changes in government, a series of revolutions (1848) and rising nationalist movements in Germany, Italy and elsewhere saw European rivalries and tensions increase again in the mid-1800s.

During the late 19th century, European leaders continued to form, annul and restructure alliances on a regular basis. The alliance system during this period is often attributed to German chancellor Otto von Bismarck and his attitude of realpolitik.

Some individual agreements signed during this period include:

The Treaty of London (1839)

Though not a formal alliance, this multi-lateral treaty acknowledged the existence of Belgium as an independent and neutral state. Several of Europe’s great powers, including Great Britain and Prussia, were signatories to this treaty.

Belgium had earned statehood in the 1830s after separating from southern Holland. The Treaty of London was still in effect in 1914, so when German troops invaded Belgium in August 1914, the British considered it a violation of the treaty.

The Three Emperors’ League (1873)

The Three Emperors’ League was a three-way alliance between the ruling monarchs of Germany, Austria-Hungary and Russia. It was engineered and dominated by the Prussian statesman Otto von Bismarck, who saw it as a means of securing the balance of power in Europe.

Disorder in the Balkans undermined Russia’s commitment to the league, which collapsed in 1878. The Three Emperors’ League, without Russia, came to form the basis of the Triple Alliance.

The Dual Alliance (1879)

The Dual Alliance was a binding military alliance between Germany and Austria-Hungary. It required each signatory to support the other if one was attacked by Russia. It was signed after the collapse of the Three Emperors’ League and during a period of Austro-Russian tension in the Balkans. 

The Dual Alliance was welcomed by nationalists in Germany, who believed that German-speaking Austria should be absorbed into greater Germany.

The Triple Alliance (1882)

This complex three-way alliance between Germany, Austria-Hungary and Italy was motivated chiefly by anti-French and anti-Russian suspicions and sentiment.

Each of the three signatories to the Triple Alliance was required to provide military support to the others, if one was attacked by two other powers – or if Germany and Italy were attacked by France.

Italy, a newly formed nation that was weak militarily, was viewed as a minor partner in this alliance.

The Franco-Russian Alliance (1894)

This military alliance between France and Russia restored cordial relations between the two imperial powers. It was, in effect, a response to the Triple Alliance, which had isolated France.

The signing of the Franco-Russian Alliance was an unexpected development that thwarted German plans for mainland Europe. The alliance angered Berlin and triggered a more aggressive shift in its foreign policy.

The Franco-Russian Alliance also provided economic benefits to both signatory nations. It gave Russia access to French loans and provided French capitalists with access to Russian mining, industry and raw materials. This was an important factor in the industrialisation of Russia over the next two decades.

The Entente Cordiale (1904)

Meaning ‘friendly agreement’, the Entente Cordiale was a series of negotiations and agreements between Britain and France, finalised in 1904.

The Entente ended a century of hostility between the two cross-channel neighbours. It also resolved some colonial disagreements and other minor but lingering disputes.

The Entente was not a military alliance since neither signatory was obliged to provide military support for the other. Nevertheless, it was seen as the first step towards an Anglo-French military alliance.

The Anglo-Russian Entente (1907)

This agreement between Britain and Russia eased tensions and restored good relations between London and Saint Petersburg.

Britain and Russia had spent much of the 19th century as antagonists. They went to war in the Crimea (1853-56) and later twice neared the brink of war.

The Anglo-Russian Entente resolved several points of disagreement, including the status of colonial possessions in the Middle East and Asia. It did not involve any military commitment or support.

The Triple Entente (1907)

This treaty consolidated the Entente Cordiale and the Anglo-Russian Entente into a three-way agreement between Britain, France and Russia.

Again, The Triple Entente was not a military alliance – but the three Ententes of 1904-7 were important because they marked the end of British neutrality and isolationism.

A Venn diagram depicting the network of alliances in 19th and 20th century Europe

Secrecy and hidden clauses

Unlike most multilateral agreements today, these alliances and ententes were formulated behind closed doors and only revealed to the public after signing.

Some governments even conducted negotiations without informing their other alliance partners. The German chancellor Bismarck, for example, initiated alliance negotiations with Russia in 1887 without informing Germany’s major ally, Austria-Hungary.

Some alliances also contained ‘secret clauses’ that were not publicly announced or placed on record. Several of these secret clauses only became known to the public after the end of World War I. The secretive nature of alliances only heightened suspicion and continental tensions.

A depiction of the two alliance blocs, each pulling against the other

Secret clauses

An additional factor in the outbreak of war were changes to European alliances in the years prior to 1914. A clause inserted into the Dual Alliance in 1910, for example, required Germany to directly intervene if Austro-Hungary was ever attacked by Russia.

These modifications were ostensibly small but they further strengthened and militarised alliances. It is debatable whether these changes increased the chances of war or simply reflected the rising tensions of the period.

The impact of the alliance system as a cause of war is often overstated. Alliances did not, as is often suggested, make war inevitable. These pacts and treaties did not disempower sovereign governments or drag nations into war against their own will.

The authority and final decision to mobilise or declare war still rested with national leaders. It was their moral commitment to these alliances that was the telling factor. As historian Hew Strachan put it, the real problem was that by 1914, “nobody was prepared to fight wholeheartedly for peace as an end in itself”.

A historian’s view:
“Models of the war’s causality have often expressed contemporary international relations. During the Cold War and the division of the world into two, there was a tendency to view international relations before 1914 as bipolar, and divided between two rigidly separated and rival blocs in which power, prestige and security were key determinants; and in which emphasis was placed on the alliance system in the war’s causes… Analysis turned on how far war was accidental (or ‘system generated’) and how far it was willed by governments.”
John Horne

alliance system

1. The alliance system was a network of treaties, agreements and ententes that were negotiated and signed prior to 1914.

2. National tensions and rivalries have made alliances a common feature of European politics, however, the alliance system became particularly extensive in the late 1800s.

3. Many of these alliances were negotiated in secret or contained secret clauses, adding to the suspicion and tension that existed in pre-war Europe.

4. The Triple Alliance (Germany, Austria-Hungary and Italy) formed the basis of the Central Powers, the dominant alliance bloc in central Europe.

5. Britain, France and Russia overcame their historical conflicts and tensions to form a three-way entente in the early 1900s.

Title: “Alliances as a cause of World War I”
Authors: Jennifer Llewellyn, Steve Thompson
Publisher: Alpha History
Date published: August 9, 2017
Date accessed: May 08, 2023
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