Why Did a War Between Austria-Hungary and Serbia Become a European War in 1914?

Why did a war between Austria-Hungary and Serbia become a European war in 1914?

On June 28, 1914, Franz Ferdinand, Archduke of Austria and heir to the Austro-Hungarian throne, was assassinated in Sarajevo by Gavrilo Princip, a Bosnian Serb student. The assassination sparked little initial concern in Europe. The Archduke himself was not terribly popular, least of all in the Austro-Hungarian Empire. While there were riots in Sarajevo following the Archduke's death these were largely aimed at the Serbian minority. Though this assassination has been linked as the direct trigger for World War I, the war's real origins lie further back, in the complex web of alliances and counterbalances that developed between the various European powers after the defeat of France and formation of the German state under the leadership of Otto von Bismarck in 1871. So why exactly did a war between Austria-Hungary and Serbia spiral out of control and become a European war in 1914?

Franz Ferdinand had limited political influence. He was Emperor Franz Joseph's nephew, and became the heir when Franz Joseph's son killed himself in 1889 (his sisters could not take the throne). This position conferred less power than one might think. Franz Ferdinand's wife, Sophie Chotek, was a Bohemian noblewoman, but not noble enough to be royal. She was scorned by many at court, and their children were out of the line of succession (Franz Ferdinand's brother Otto was next). Franz Ferdinand had strong opinions, a sharp tongue and many political enemies. He favored "trialism," adding a third Slavic component to the Dual Monarchy, in part to reduce the influence of the Hungarians. His relations with Budapest were so bad that gossips blamed the killing on Magyar politicians. So if Ferdinand was relatively unimportant politically speaking, why did his killing result in a war between Serbia and Austria-Hungary?

As soon as Ferdinand's assassination unfolded, the Austrian police and the courts undertook a wide-ranging series of arrests and investigations. Hundreds of people were arrested or questioned, sometimes violently. Twenty-five people were finally tried and convicted, though only a few were executed, because so many of the defendants were minors. The early Austrian deliberations included another, calculated element that shows their limited interest in peace: in weighing the merits of a military response, Vienna first sought the reaction of her German ally. The Austrian ambassador in Berlin found that the Germans, especially Kaiser Wilhelm, supported a war to punish Serbia and offered their full support. This was in clear contrast to events during the Balkan War of 1912, when Berlin refused to back Vienna in any intervention. Like the Austrians, the Germans feared a future war with Russia, and preferred to fight soon, before their enemies grew stronger.

In the first place, both governments believed that their prestige and credibility were on the line, not only in the international community, but at home. For the Austrians, a personal attack on the royal family required a strong response, especially if the assassins were Serbs, who had defied the Dual Monarchy during the Pig War, been labelled as traitors during the Friedjung Trial, and recently destroyed southeastern Europe's other dynastic empire (the Ottomans). Failure to act in the summer of 1914 invited greater turmoil later.

On the international stage, both sides were one defeat away from being marginalised: Austria-Hungary had no intention of replacing the Ottoman Empire as the "Sick Man of Europe" and Serbia refused to