Germany wasn't the only one to blame for starting the war. Austria-Hungary was also largely to blame because they had many problems with their country's nationalism. The Serbs, who lived in Austria-Hungary, also wanted to unite Serbia. This caused tension within Austria-Hungary, which were not at all happy with Serbia and so it is said that the war started. The only setback was that Serbia was Russia's ally and from the moment Russia attacked it, Russia would defend it. This would make Austria-Hungary have to fight both. A well-known cause for the outbreak of World War I was the conflict in the Balkans. If we look at the 4 main causes mentioned in the introduction (M-A-I-N), nationalism and militarism wanted to maintain their independence. This Balkan war consisted of a military alliance against the Ottoman Empire. The success of this war surprised most European powers. These were one of the main reasons why we could say that Germany was not the only culprit, although there are many other arguments.