The Balkan Powder Keg: Austria-Hungary's War Declaration On Serbia

On June 28, 1914, Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, and his wife, Sophie, were assassinated by Gavrilo Princip, a Bosnian Serb nationalist. This event, following years of tensions between Austria-Hungary and Serbia, led to Austria-Hungary issuing an ultimatum to Serbia on July 23, 1914, demanding the suppression of anti-Austrian propaganda and the right to conduct an investigation into the assassination. Although Serbia accepted most demands, Austria-Hungary was not satisfied and broke diplomatic relations on July 25. With the support of its ally, Germany, Austria-Hungary declared war on Serbia on July 28, 1914, marking the beginning of World War I.

Assassination of Archduke Franz Ferdinand

The assassination of Archduke Franz Ferdinand, heir presumptive to the Austro-Hungarian throne, and his wife, Sophie, Duchess of Hohenberg, on June 28, 1914, was a key catalyst for World War I.

Archduke Franz Ferdinand was in Sarajevo, Bosnia, to attend military exercises. Bosnia-Herzegovina had been annexed by Austria-Hungary a few years earlier, against the wishes of neighbouring Serbia, which also coveted the territory. The Archduke's visit was, therefore, a provocation to Serbian nationalists.

On the day of the assassination, a motorcade was scheduled to take the Archduke and his wife from the train station to Sarajevo's Town Hall. The procession route had been published in advance, and six armed irredentists—five Bosnian Serbs and one Bosnian Muslim—coordinated by Danilo Ilić, were lying in wait along the route. At 10:10 a.m., Nedeljko Čabrinović threw a hand grenade at the motorcade, damaging the car behind and injuring its occupants. Later that morning, as the couple were driving back to visit the wounded in the hospital, Gavrilo Princip managed to shoot and kill Franz Ferdinand and Sophie. Čabrinović and Princip took cyanide but it only sickened them, and both were arrested.

The assassination precipitated a rapid descent into World War I. Austria-Hungary gained German support for punitive action against Serbia and sent an ultimatum to Serbia, worded in a way that made acceptance unlikely. Serbia proposed arbitration to resolve the dispute, but Austria-Hungary instead declared war on July 28, 1914, exactly a month after Ferdinand’s death.

The conflict soon escalated, and by the following week, Germany, Russia, France, Belgium, Montenegro and Great Britain had all been drawn into the war. Other countries like the United States would enter later. Overall, more than 16 million people—soldiers and civilians—died in fighting that lasted until 1918.

Austria-Hungary's ultimatum to Serbia

On the evening of July 23, 1914, nearly a month after the assassination of Archduke Franz Ferdinand and his wife by a young Serbian nationalist in Sarajevo, Bosnia, Austria-Hungary issued an ultimatum to Serbia. The ultimatum was delivered by the ambassador of the Austro-Hungarian Empire to Serbia, Baron Giesl von Gieslingen, to the Serbian foreign ministry.

The ultimatum contained six concrete demands, which were designed to be unacceptable to Serbia. These demands included:

• The Serbian government was required to officially distance itself from the political campaign to unite the southern Slav peoples under Serbian leadership, which challenged the territorial integrity of Austria-Hungary.
• The purging of the Serbian army and civil service of anti-Austrian agitators.
• The suppression of anti-Austrian propaganda in the Serbian press.
• The Serbian government was called upon to track down and take legal proceedings against extremist secret organisations operating against Austria.
• Austrian officials should take part in the investigation into the assassination and in the hunting down and prosecution of the ringleaders on Serbian territory, which would infringe on Serbia's state sovereignty.
• Serbia was to suppress all anti-Austrian propaganda and to take steps to root out and eliminate terrorist organisations within its borders.

Additionally, the ultimatum included a 48-hour deadline for a response. It was clear that if Serbia did not comply, Austria-Hungary would break off diplomatic relations and that military action would likely follow.

Serbia's response to the ultimatum effectively accepted all terms except one: it refused to allow Austria-Hungary to participate in any internal inquiry, stating that this would violate its Constitution and criminal procedure law. Despite this, Austria-Hungary was not satisfied and broke off diplomatic relations with Serbia on July 25, 1914. Three days later, on July 28, Austria-Hungary declared war on Serbia, marking the beginning of World War I.

Russia's mobilisation

Russia's Partial Mobilisation:

On 24-25 July 1914, even before Serbia's rejection of the Austro-Hungarian ultimatum, Russia's Council of Ministers ordered a secret partial mobilisation. This involved over a million men of the Russian Army and the Baltic and Black Sea Fleets. This mobilisation was directed against Austria-Hungary and was intended to deter them from attacking Serbia. Russia's military leadership believed that a forceful response was necessary, suspecting that Austria-Hungary's grievance against Serbia was a pretext orchestrated by Germany.

Impact on Serbia:

Russia's partial mobilisation increased Serbia's willingness to defy the Austro-Hungarian ultimatum. It also sent a strong signal to Austria-Hungary and Germany, demonstrating Russia's commitment to supporting Serbia.

Reactions in Europe:

The partial mobilisation caused concern among other European powers, particularly Germany. Germany's leadership, who had not anticipated the possibility of fighting Russia before confronting France, was alarmed by this development. They urged Austria-Hungary to attack Serbia quickly to localise the war and avoid drawing in Russia.

Full Mobilisation and War:

On 28 July 1914, Russia ordered full mobilisation in response to Austria-Hungary's declaration of war on Serbia. This further escalated tensions and pushed Europe closer to war. On 1 August, Germany declared war on Russia, and Russia's ally, France, ordered its own general mobilisation that same day, and on 3 August, France and Germany declared war on each other. The German army’s planned invasion of neutral Belgium, announced on 4 August, prompted Britain to declare war on Germany.

Impact on World War I:

Germany's declaration of war on Russia and France

The assassination of Archduke Franz Ferdinand and his wife, Sophie, on 28 June 1914, set off a chain of events that led to Germany's declaration of war on Russia and France. The complex web of alliances in Europe at the time meant that the conflict quickly escalated beyond the Balkans.

Austria-Hungary, with the backing of Germany, delivered an ultimatum to Serbia, which was seen as a harsh set of demands designed to provoke a war. Russia, a supporter of Serbia, responded by ordering a partial mobilisation of its armed forces. This alarmed the German leadership, who had not anticipated the possibility of having to fight Russia before France.

Germany's war plans, including the Schlieffen Plan, were based on the idea of avoiding a two-front war at all costs. The plan relied on Germany's ability to invade France quickly and knock them out of the war before turning its attention to Russia. However, Germany's mobilisation and invasion of Belgium, a neutral country, brought Britain into the war as well, which further complicated the situation.

On 1 August 1914, Germany declared war on Russia, and on 3 August, it declared war on France. Germany's declaration of war on Russia and France was part of its strategy to engage in a two-front war and attempt to seize territory quickly, establishing a buffer and strategic depth to the east. Germany wanted to avoid a protracted conflict on its own soil and sought to disrupt the Russian economy and industry instead.

The German leadership recognised the vulnerability of facing attacks from both the west (France) and the east (Russia) and sought to take the initiative. However, the entry of Britain into the war and the mobilisation of Russian forces complicated their plans. Germany's declaration of war on Russia and France was a pivotal moment in the escalation of the conflict, ultimately leading to a global war with devastating consequences.

Germany's invasion of Belgium

The invasion of Belgium by Germany in 1914 was a significant event during World War I, marking the beginning of a military occupation that lasted until 1918. On August 2, Germany presented an ultimatum to Belgium, demanding free passage for its troops to cross the Belgian borders. When King Albert I refused, Germany invaded Belgium on August 4, just days after declaring war on Russia.

The German army rapidly advanced into Belgium, besieging and capturing the fortified cities of Liège, Namur, and Antwerp. This forced the Belgian army, supported by French and British allies, to retreat to the west. The swift German invasion resulted in the Belgian government going into exile, while King Albert I and the Belgian Army continued to resist along the Western Front. By October 1914, the German advance was halted near the French border, with most of Belgium already under German control.

The invasion and subsequent occupation of Belgium had significant consequences. It led to an economic collapse in Belgium, with shortages, unemployment, and widespread suffering among the civilian population. The German occupation administration imposed repressive measures, including the deportation of Belgian workers to Germany and forced labour on military projects. Additionally, war crimes were committed by German troops, with massacres and executions of Belgian civilians. The invasion also triggered Britain's entry into the war, as Germany's violation of Belgian neutrality served as a casus belli.

The occupation of Belgium was marked by resistance movements, which attempted to sabotage military infrastructure, gather intelligence for the Allies, and print underground newspapers. Belgium's colonial possession in Africa, the Belgian Congo, remained loyal to the Allies. The end of the occupation came with the armistice of November 1918, as the Belgian Army advanced into the country to restore order.

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