Serbian army's retreat through Albania

Following the October 1915 invasion of Serbia during World War I at the hands of German, Austro-Hungarian and Bulgarian armies, the Serbian army retreated through Albania, an event sometimes called the Albanian golgotha (Serbian: Албанска голгота/Albanska golgota). During the long march, some 240,000 retreating Serbs died from the cold, starvation, disease and at the hands of Albanian tribesmen. The march through the Albanian mountains had decimated its rank and contributed to the horrendous losses the Serbs had suffered in the First World War – the highest per capita of any country.

On 28 June 1914, Gavrilo Princip, a Bosnian Serb student and member of Young Bosnia, assassinated the heir to the Austro-Hungarian throne, Archduke Franz Ferdinand of Austria in Sarajevo, Bosnia. The political objective of the assassination was to break the Austro-Hungarian's south-Slav provinces off from the Austro-Hungarian Empire. The assassination triggered a chain of events that embroiled Russia and the major European powers. This began a period of diplomatic manoeuvring among Austria-Hungary, Germany, Russia, France, and Britain called the July Crisis. Wanting to finally end Serbian interference in Bosnia and the Balkans, Austria-Hungary delivered the July Ultimatum to Serbia, a series of ten demands intentionally made unacceptable, intending to provoke a war with Serbia. When Serbia agreed to only eight of the ten demands, Austria-Hungary declared war on 28 July 1914.

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