The one action that put every major force into hostility. Probably one of the most important, yet overlooked, moments in history. The assassination of Archduke Franz Ferdinand. He was the heir to the throne of the Austria-Hungarian Empire. In June of 1914, he was assassinated by a Serbian group who was standing up for the land they wanted that was being taken by the Asutria-Hungarians. Once he was assassinated, the Austria-Hungarians declared war on Serbia. Once this happened, the mutual defense agreements took place and before anyone knew it, the War to End All Wars had started which would leave to over 30 million human deaths. Overall, I believe that World War 1 is one of the most influential events in history. When you think about it, the assassination of Archduke Franz Ferdinand did not cause only the First World War. It could be held responsible for creating the tensions after World War 1 that caused World War 2. The causes of World War 1 not only affected its time period, but created a lasting impact. Things like the Cold War and Vietnam were also based on similar things such as arms races and nationalism. Looking back at it now, you can see how important not only the war was, but the causes and the things that happened before