The First World War (1914–1918)

The assassination of Archduke Franz Ferdinand at Sarajevo on 28 June 1914 was the immediate trigger, but it was not the only cause. Europe had accumulated nationalist tensions, imperial rivalries, military competition, alliance commitments and repeated crises. A strong historical explanation distinguishes these long-term conditions from the event that triggered the July Crisis.

Nationalism increased rivalry between states and destabilised the Balkans. France resented the loss of Alsace-Lorraine to Germany, while Serbian and South Slav nationalism worried Austria-Hungary. Imperial competition for colonies, markets and prestige deepened suspicion, illustrated by the Moroccan crises. Militarism expanded armies, navies and mobilisation plans; Anglo-German naval rivalry became a major symbol. The Triple Alliance and Triple Entente shaped security calculations. In the Balkans, Serbian ambitions and Austro-Russian rivalry made local disputes dangerous. After Sarajevo, Austria-Hungary received German backing, issued Serbia an ultimatum and declared war on 28 July. Russian mobilisation, German declarations of war on Russia and France, the invasion of Belgium and British entry widened the confrontation.

Germany hoped to defeat France quickly in the west before concentrating against Russia. German forces advanced through Belgium, but the advance was halted at the First Battle of the Marne in September 1914. A continuous defensive front developed and armies dug elaborate trench systems. Machine guns, artillery, barbed wire and prepared positions made frontal attacks extremely costly, producing a prolonged war of attrition. Verdun and the Somme in 1916 became major examples of industrial warfare and enormous loss. Tanks appeared on the Somme but early models were limited and unreliable.

The war extended beyond the Western Front. Germany defeated Russian forces at Tannenberg in 1914 while Russia continued fighting Germany and Austria-Hungary. The Ottoman Empire joined the Central Powers, and campaigns occurred at Gallipoli, in the Middle East and in Africa. African soldiers and carriers supported operations in East Africa under extremely difficult conditions. At sea, Britain used blockade while Germany increasingly relied on U-boats. The Battle of Jutland in 1916 did not remove Britain's ability to maintain its blockade.

The balance changed in 1917–1918. Revolution destabilised Russia and the Bolshevik government left the war through the Treaty of Brest-Litovsk in March 1918. The United States entered the war against Germany in April 1917; unrestricted submarine warfare was an important factor in worsening US-German relations. Germany launched major western offensives in spring 1918 but failed to achieve decisive victory. Allied counterattacks, increasing American support, shortages, blockade, military setbacks and political unrest weakened the Central Powers. The armistice took effect on 11 November 1918. The Treaty of Versailles followed in 1919.

The war caused enormous human suffering. Millions of military personnel and civilians died, while many more were wounded, disabled, displaced or psychologically affected. Economies were strained by borrowing, taxation, military production and destruction. Europe emerged weakened while the United States strengthened its relative financial and economic position.

The German, Austro-Hungarian, Ottoman and Russian imperial orders collapsed or were transformed. New states and borders appeared in central and eastern Europe, while revolution produced a communist government in Russia. At the Paris Peace Conference, the Treaty of Versailles imposed territorial changes, military restrictions, reparations obligations and a war-responsibility clause on Germany. Versailles later became a major German grievance, but it should not be treated as the single cause of the Second World War.

The devastation encouraged creation of the League of Nations to promote international cooperation and collective security. Former German colonies and former Ottoman territories were redistributed through the mandates system, so colonial control continued in new forms. Africa had been affected through military service, carrier labour, resource mobilisation, direct campaigns in some regions and post-war territorial redistribution. Wartime experience contributed over time to changing political consciousness, but the war did not immediately end colonial rule.

The assassination at Sarajevo did not mechanically cause a world war. What made the July Crisis so dangerous was the interaction between alliance commitments, military planning and political choices. Austria-Hungary wanted to weaken Serbia and secured strong German backing before issuing a deliberately severe ultimatum. Serbia accepted many demands but rejected provisions that would have compromised its sovereignty. Russia, presenting itself as a protector of Serbia and seeking influence in the Balkans, moved toward mobilisation. German leaders interpreted Russian mobilisation through war plans that assumed Germany would have to defeat France quickly before turning east. Germany therefore declared war on Russia and France and invaded neutral Belgium. Britain entered after the violation of Belgian neutrality and because a German-dominated western Europe threatened British strategic interests. The sequence shows why historians distinguish background causes from escalation. Alliances did not force governments to fight automatically; leaders made decisions within an international system in which delay, mobilisation and fear of strategic disadvantage narrowed the space for compromise.

The Armistice of 11 November 1918 ended the fighting, but the peace settlement created new disputes. At Paris, the victorious powers pursued different goals. France emphasised security against another German attack; Britain sought a workable European balance and protection of imperial interests; the United States promoted principles associated with President Woodrow Wilson, including a new international organisation. The Treaty of Versailles reduced German military power, transferred territory, imposed reparations obligations and included the war-guilt clause. Other treaties dismantled the Austro-Hungarian and Ottoman imperial orders and recognised or reshaped states in central and eastern Europe. The settlement promoted national self-determination selectively: some European peoples gained states, while colonial peoples did not receive equivalent independence. Former German colonies became League mandates administered by victorious powers. This contradiction matters for African history. The post-war order spoke the language of international responsibility while preserving imperial rule. Resentment over the settlement, economic instability and unresolved national questions later became part of the background to the Second World War, though Versailles alone cannot explain the conflict of 1939.

💡 NOTE

Misconception alert: Sarajevo was the immediate trigger, not a complete explanation of why a European crisis became a world war. A strong answer separates the assassination and July Crisis from longer-term nationalism, imperial rivalry, militarism, alliance commitments and Balkan instability.

💡 NOTE

Kenya and the wider East African region were drawn into the First World War through the East African campaign, military recruitment, carrier labour, requisitioning and economic disruption. African communities experienced the conflict differently from European battlefronts, and wartime service and hardship later contributed to changing political awareness. When explaining impact, distinguish direct wartime effects from the longer-term growth of anti-colonial politics; the war did not itself end colonial rule.

For learners in Kenya, the East African campaign is essential because the First World War was not only fought in European trenches. British forces and their allies campaigned against German East Africa, while large numbers of Africans served as soldiers, porters and carriers. The Carrier Corps moved food, ammunition and equipment across difficult terrain where roads and railways were limited. Disease, exhaustion, inadequate supplies and displacement made the campaign extremely costly for African communities. Livestock, food and labour could be requisitioned for the war effort, while trade and normal production were disrupted. The campaign also demonstrates the unequal structure of colonial warfare: European empires made strategic decisions, but African populations supplied much of the labour and endured major social and economic costs. In later political memory, wartime service, taxation, labour demands and exposure to wider regions contributed to changing expectations, although anti-colonial nationalism developed through many causes and should not be reduced to wartime experience alone.

Causes: nationalism, imperial rivalry, militarism and arms competition, alliances, Balkan instability, Sarajevo and the July Crisis. Course: failed rapid-war plans, Marne, trenches and attrition, global and eastern fronts, blockade and U-boats, Russia's withdrawal, US entry, 1918 offensives and Allied counterattack, then the Armistice. Results: human loss, economic strain, collapse of empires, Russian Revolution, new borders, Versailles, League of Nations, mandates and changes in international power.

📋 ACTIVITY

Create a three-part timeline labelled Causes, Course and Results. Add Sarajevo, the July Crisis, Marne, trench warfare, Verdun and the Somme, US entry, Russian withdrawal, the 1918 offensives, the Armistice and Versailles. Beside each event, write one sentence explaining its significance.