World War I, started with two pistol shots. On June 28, 1914, Gavrilo Princip, a young Bosnia student, shot and killed the Archduke Francis Ferdinand, heir to the throne of Austria-Hungary, and his wife Sophie. They were killed in Sarajevo, the capital of the Austrian province of Bosnia. Princip's group, Young Bosnia, wanted independence from Austria-Hungary. Austria-Hungary believed Serbia to have been involved in the plot to kill Ferdinand and declared war on Serbia, July 28, 1914. Thus the First World War, the Great War, or The War to End All Wars began.

There were other circumstances which precipitated World War I. A strong movement toward nationalism was growing, people wanting their own national government with people of the same nationality and language. Countries were competing for colonies and other lands. Economic imperialism propelled the industrial economy. Countries sought to gain control of raw materials and
to open new markets for their prducts. There was mistrust. Countries formed military alliances and conducted secret diplomacy. A naval arms race developed between Germany and Great Britain.