World War 1 World war 1 was a world conflict that broken in the year of 1914-1918. Some general causes why the war can happened, like the conflict among Europe countries, the existence of military alliance Europe and the appearance of arm race. But the direct cause of the war was the murderer of Archduke Franz Ferdinand of Austria in Sarajevo. It happened when the Archduke, Franz Ferdinand was visiting the military training he was murderer by, Gavrillo Princip . Because for Serbia, the military training that had done by Austrian army was assumed as to show of Austrian army’s power. So because that accident, Austria demanded Serbia to give the murderer in one month. However, that demand was neglected by Serbia supported by Russia. For that reason, Austria declared war to Serbia. And after that, because military alliance caused the conflict soon spread worldwide. The war had involved many country and covered large area, like France, Germany, British, USA, Japan,etc....