What Caused the First World War?

Discover: Explore the map to see what Europe looked like in 1914.

Map Data: Kropelnicki, Jeffrey; Johnson, Grace; Kne, Len; Lindberg, Mark. (2022). Historical National Boundaries. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/146x-1412.

A map of Europe in 1914 would look very different from a map of Europe today. Eastern Europe, especially, was divided amongst a series of empires: the German empire, the Austro-Hungarian empire and the Ottoman empire. These empires, along with Western European countries, were in constant competition with one another. Indeed, decades of imperial rivalries, economic competition, nationalism, and instability all led to a very fragile and unstable peace in Europe at the turn of the 20th century.

We can refer to the following as the MAIN causes of WWI: Militarism, Alliances, Imperialism and Nationalism.

MAIN Causes of the First World War

Militarism

During the 19th century and leading up to the First World War, European countries spent considerable resources maintaining an army even in times of peace. Each country had to make sure they would be ready as quickly as possible in case they were attacked. However, the extent to which they prepared for an eventual conflict varied widely.

The largest armies were in Europe, where most of the fighting took place. Comparing the number of soldiers enlisted to the total population, France had the largest army per capita at the time with 11% of its population enrolled. The Russian Empire had the largest army in absolute numbers, but this massive army only represented 0.4% of its population. In comparison, Canada’s army at the time was very small: only a couple of ships and approximately 3 110 soldiers for a population of less than 8 million people.

Amassing such large armies did little to preserve the peace and left nations wary of their neighbours.

Alliances

Throughout the 19th and early 20th century, various European countries formalized economic and political agreements with one another. These agreements had many benefits for the countries involved. Military alliances specifically allowed for additional protection and support to countries faced with threats. However, countries sometimes agreed to terms of the alliances in secret, or without consulting the other countries that they already had agreements with.

This led to a complex system of alliances throughout Europe. In general, two main alliances emerged at the start of the war: The Triple Alliance of Germany, Austria-Hungary, and Italy, and the Triple Entente, formed by Britain, France, and Russia. In addition to these nations, many other smaller countries gravitated towards them: Serbia, Romania and Greece, among them. If any one country found themselves at war, the others in their alliance would likely follow suit.

A map of European alliances in 1914.

Imperialism

Many European empires lost their colonies in the Americas during the 1700s and 1800s, yet the Middle East, Africa and Asia were still sought after territories. By the 19th century, large portions of Africa had been taken over by France, Great-Britain, Belgium and Germany. In Asia, many great ancient empires had fallen, conquered by European powers: the Qing Dynasty in China, the Sikh Empire in India, the Nguyễn dynasty in Vietnam, and many others. Finally, in the Middle East, the Ottoman Empire controlled most of the access points to the territories in the east – directly controlling the access to Asia.

Conquering these new territories was not enough for the European empires, however.  Territorial expansion was a means of showing their might and filling their coffers, and they always wanted more. The Ottoman Empire was slowly collapsing at the time and European nations eyed their territories, hoping to position themselves as the strongest powers in the world, at the cost of African, Asian and Middle Eastern nations.

Cartoon from Harper’s Weekly, 1885 (Landesbibliothekszentrum Rheinland-Pfalz).

Nationalism

European militarism and imperialism were often fueled by nationalism, a belief in one’s superiority and natural right to wealth, territory and power. However, having an empire usually means subsuming smaller nations into the larger empire and controlling their interests, which leads to another form of nationalism: the desire for self-determination, to have control of your own nation.

Bosnia, for example, was not a nation of its own in 1914, but rather was part of the Austro-Hungarian empire. On June 28, 1914, in Sarajevo, Bosnia, a Serbian nationalist, who wanted to create a unified South Slavic state and liberate Serbians living under Austro-Hungarian rule, assassinated Archduke Franz Ferdinand, who was to become the future King of Austria-Hungary. The assassin was part of an extremist group that wanted Serbian power in the Balkans and intended to break up the Austro-Hungarian Empire. In return, Austria-Hungary believed the Serbian government was involved in the murder and declared war. This was the spark that ultimately ignited the war.

Franz Ferdinand and his wife Sophie shortly before their assassination (Bundesarchiv).

How did Canada get involved?

When the Austro-Hungarian Empire declared war on Serbia, many countries were bound by treaties and thus obligated to join the conflict. Russia, allied to Serbia, declared war on the Austro-Hungarian Empire. Germany, allied with the Austro-Hungarians, then stepped in and demanded a promise of peace from Russia and its ally, France. When the Germans received no reply, they declared war on Russia on August 1, 1914, and on France on August 3, 1914. 

On its way to France, the German army invaded Belgium on August 3rd, 1914. Britain, an ally of France and supporter of Belgian neutrality, demanded that the Germans withdraw from Belgium and that Germany observe the Treaty of 1839 which declared Belgium a neutral country. Despite the ultimatum from the British, the Germans continued their invasion and Britain declared war on Germany on August 4th.

Sheet music for the patriotic war song “Our Mother is Calling” (Toronto Public Library).

Many European countries were major colonial powers at the time. Their involvement in the conflict therefore meant that their colonies were automatically at war as well. As a result, the First World War involved people from all over the world. Although the fighting mainly took place in Europe, Africa and the Middle-East also saw their own theatres of war.

Canada was a self-governing Dominion of the British Empire, but did not fully determine or control its own foreign affairs. Therefore, Canada was obliged to enter the War alongside Britain, which asked Canada to deploy 25,000 soldiers. The Canadian Government thought that the might of the British Empire would make for a short-fought war with Germany. Little did they know it would last four long years and enlist 619 636 Canadians, almost 13% of Canada’s population of 8 million.

Enlistment

When war broke out, Canadians rushed to enlist in large numbers. Many chose to enlist out of feelings of patriotism and the desire to fight a just war against German aggression. Some also wished to enlist for adventure and travel. Newspapers, posters, clergymen and politicians encouraged men to enlist as a duty to King and Country.

Recruiting soldiers outside of City Hall in Toronto, Ontario (Library and Archives Canada).

Early in the war, volunteers overwhelmed Canadian recruiting offices. Recruiters followed government-mandated medical requirements and turned away numerous men whom they deemed “unfit” or “undesirable” whether due to their age, height, medical history or even the colour of their skin. While there was no government policy on the ethnicity of volunteers, many recruiters ascribed to the belief that this was a “white man’s war” and turned away Asian, Indigenous and Black Canadians. This decision was, however, frequently left to the discretion of the recruiting officer and some recruiting officers accepted all eligible fighters, including Indigenous, Black and Asian Canadians, amongst their ranks. As the war progressed and the troops overseas faced heavy losses, Canada needed more soldiers and loosened its restrictions on recruitment.

Did you know?

The youngest recorded age of a Canadian soldier that enlisted in the CEF was 11. The oldest was 78. In both cases, they lied about their age.

Discover: For some, enlistment was a simple process. Others went to great lengths to enlist, showing a powerful determination to fight for what they felt was right. Explore the stories below to learn more

Regimental Case Studies