H Cochran writes the fear that gripped Austria was if there were "-created states in the Balkans, the Austria-Hungary monarchy would go to pieces" (M.C Cochran, The real causes of war). Thus Slav nationalism could not be tolerated by the Austrians, this belief is important in the lead up to war as it dictates Austria's measures against Serbia later on. Russia had also great interests in the Balkans as they would greatly benefit from the collapse of the Austrian-Hungarian Empire as well they wanted to advance their policy of "pan-Slavism", aimed at uniting and supporting their fellow Slavs. .
All this transformed a fairly poor and backward region into what some historians name the "powder-keg of Europe". Historian Suzanne Karpilovsky summarised that the main conflict was "the ardent Panslavism of Serbia and Russia's willingness to support its Slavic brother conflicted with Austria-Hungary's Pan-Germanism". It was the struggle of nationalist movements in the Balkans, combined with Slavic hatred for the Austrians resulted in the Serbian nationalist group, the Black-hand in organising the assassination of the heir of Austria-Hungarian Empire, Archduke Fez Ferdinand in Sarajevo on the 28th July 1914. This was not a main long-term cause of the Great War though it was important as the assassination basically begun the "July crisis" which begin the final stages to all out war. Another factor to why nationalist resistance to foreign rule resulted to war was that they disturbed the peace that Europe had since the last major European war in 1871. This view is supported by historian Stewart Ross when he writes "the short lived calm (in Europe) ended in the Balkans (Ross, Steward, Causes and Consequences of the first World War) The opposition of nationalists, especially Slavic ones, towards imperial control not only managed to drag two major powers (Russia and Austria-Hungary) as well as their major allies into heated conflict but also provided the final spark for war in the assassination of the Archduke in Sarajevo.
