To what an extent were the Balkans a major cause for the outbreak of the WWI?

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The Balkans consisted of Albania, Bulgaria, Greece, Montenegro, Romania, and Serbia. Each of these newly formed countries were strong at nationalism and they wanted to extend their borders. In 1912, all these countries except from Albania and Romania formed the Balkan league, with the aim of driving the Turks out of Europe. The Ottoman Empire was occupied with an internal revolution and a war with Italy because of control over some land in North Africa. With this opportunity, the Balkan League attacked them and this became known as the First Balkan War. The fast success of the League made the big powers anxious, especially Austria, because of how Serbia was growing. There was an agreement in the Treaty of London that made Bulgaria feel cheated because of its share of territory, attacked Serbia. The other 3 of the League supported Serbia and in less than a month Bulgaria was badly defeated. The following agreement, in the Treaty of Bucharest, gave more land to Serbia, Greece and Montenegro. Clearly, after this Second Balkan War, Austria was the loser, not because they have lost any land or suffered disadvantages for their state, but because of the new power and strength of Serbia, and was now in a position to resist to certain attacks.

With Austria being angry as ever because of the Balkans, and Serbia growing and expanding every minute, Austria-Hungary decided to use the Assassination of Franz Ferdinand in Serbia, as excuse to crush them and end with all their rivalry for once. Austria responded the event that happened in Serbia, in June 1914, by sending the Serbs an ultimatum. The deadline of it was some days after it was given, so there was no chance for the Serbs of getting out of this new conflict. Austria was allied to Germany, Serbia to Russia, and Russia to France; a clear example of how a simple alliance between at least 2 countries, could make a local trouble, to become a general war. The first army that began to mobilize, was the Russian army, immediately after this, Austria called on Germany (Aside from being allies, Germany had plans of going in war also with Russia’s ally, France, to avoid war on two fronts (Schlieffen Plan)). As Russia did not halt its preparations, the French mobilization began. Once Russia refused to demobilize, Germany declared war on Russia, France on Germany; and Britain had only one formal ally (Belgium), and as the Germans had plans of an invasion in Belgium, they had to declare war on the Germans. We can clearly see here, Fritz Fischer’s point of view and his idea of Germany having war plans before 1914, and using the assassination of Ferdinand as an excuse to finally put them into practice.

To conclude, I can say that all the long and short-term causes should be considered as essential factors for having caused the outbreak of the WWI. Nevertheless, we shouldn’t forget to consider each one of them, with different importance. There were some short-term causes that were decisive for the outbreak, but that doesn’t mean that they were more important or more relevant than others.