11.1 Alliances, Expansion, and Conflict

Alliances, Expansion, and Conflict

Europe in the early 20th century was a powder keg. Rival alliances, imperial competition, and rapid military buildup created a volatile atmosphere where even a small crisis could spiral out of control. The assassination of Archduke Franz Ferdinand in June 1914 did exactly that, dragging Europe's major powers into a catastrophic war within weeks.

Alliances and Militarization in Early 20th Century Europe

Opposing Alliances

Two rival alliance blocs divided Europe and made large-scale war far more likely.

• The Triple Alliance (1882) united Germany, Austria-Hungary, and Italy in a defensive pact. If one member was attacked, the others were obligated to help.
• The Triple Entente (1907) brought together Great Britain, France, and Russia to counter growing German power.

These alliances were supposed to deter aggression, but they actually had the opposite effect. Member nations felt emboldened to take risks in international disputes because they knew powerful allies had their backs. This meant a localized conflict, say in the Balkans, could quickly pull in every major European power.

The Arms Race

Military buildup heightened tensions and deepened suspicion across Europe.

• Germany's naval expansion (the Tirpitz Plan) directly challenged British naval supremacy. Britain had long relied on its navy to protect its empire, so Germany's shipbuilding program triggered a fierce naval arms race between the two powers.
• Russia's military modernization after its humiliating defeat in the Russo-Japanese War (1904–1905) alarmed Germany and Austria-Hungary, who worried about a stronger Russian threat on their eastern borders.
• France invested heavily in its army and built fortifications along the German border, preparing for a future conflict over Alsace-Lorraine (lost to Germany in 1871).

Beyond hardware, militarization shaped European culture. Popular literature, art, and education glorified military strength and national pride. Many political and military leaders believed war was inevitable and that striking first would be the key to victory.

Imperial Competition and the Outbreak of World War I

The Scramble for Africa

Colonial rivalries outside Europe added fuel to the fire. The Moroccan Crises (1905 and 1911) nearly brought France and Germany to war over influence in North Africa. Britain, already uneasy about Germany's global ambitions (a policy known as Weltpolitik), grew even more hostile toward Berlin.

The Balkan Powder Keg

The Balkans were the most dangerous flashpoint in Europe, where Austro-Russian rivalry and rising nationalism collided.

• Austria-Hungary's annexation of Bosnia and Herzegovina (1908) infuriated Serbia, which had its own ambitions in the region, and angered Russia, which saw itself as the protector of Slavic peoples.
• The decline of the Ottoman Empire left a power vacuum in southeastern Europe. European powers competed for influence over former Ottoman territories, and newly independent Balkan states pursued their own nationalist goals.
• The Balkan Wars (1912–1913) redrew borders in the region, strengthened Serbia, and deepened hostility between Serbia and Austria-Hungary.

The Spark: Assassination of Franz Ferdinand

On June 28, 1914, Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, was assassinated in Sarajevo, Bosnia, by Gavrilo Princip, a Bosnian Serb nationalist. What followed was a rapid chain reaction:

1. Austria-Hungary issued a harsh ultimatum to Serbia, blaming it for the assassination.
2. Serbia accepted most but not all of the demands, and Austria-Hungary declared war on Serbia (July 28).
3. Russia began mobilizing its military to support Serbia.
4. Germany, honoring its alliance with Austria-Hungary, declared war on Russia and then on France.
5. Germany invaded Belgium to execute its war plan, which brought Britain into the war in defense of Belgian neutrality.

Within six weeks of the assassination, most of Europe's major powers were at war.

Military Strategies and War Plans

Every major power entered the war with a plan. None of them worked as expected.

Schlieffen Plan (Germany)

Germany's biggest strategic fear was a two-front war against France in the west and Russia in the east. The Schlieffen Plan aimed to solve this by knocking France out quickly before Russia could fully mobilize.

• German forces would sweep through neutral Belgium and Luxembourg, loop around, and encircle the French army.
• The plan relied on speed and overwhelming force to defeat France in roughly six weeks.
• It failed for several reasons: Belgian resistance slowed the advance, Britain entered the war over the violation of Belgian neutrality, and the French and British halted the German offensive at the Battle of the Marne (September 1914).

Plan XVII (France)

France's strategy was an all-out offensive to retake Alsace-Lorraine.

• French military doctrine emphasized élan vital (offensive spirit), the belief that aggressive attacks and high morale could overcome defensive advantages.
• The plan assumed Russia would mobilize quickly and force Germany to split its forces.
• In practice, French offensives in August 1914 suffered devastating casualties against entrenched German positions.

Plan XIX (Russia)

Russia planned a two-pronged offensive into East Prussia (against Germany) and Galicia (against Austria-Hungary).

• The goal was to protect Serbia and seize the initiative before Germany could turn east.
• Slow mobilization, poor coordination between Russian armies, and supply problems led to crushing early defeats at Tannenberg and the Masurian Lakes (August–September 1914).

Britain's Naval Strategy

Britain focused on what it did best: controlling the seas.

• The Royal Navy imposed a naval blockade on Germany, cutting off imports of food and raw materials to weaken the German economy over time.
• Britain also deployed the British Expeditionary Force (BEF) to France and Belgium, though it was small compared to the continental armies.

Austria-Hungary's Campaign Against Serbia

Austria-Hungary expected a quick, punitive war against Serbia to reassert its dominance in the Balkans.

• The plan depended on German support if Russia intervened.
• Austria-Hungary underestimated both Serbian resistance and Russian willingness to mobilize, leading to early setbacks and a much longer, costlier conflict than anticipated.