World War I
In 1908, Austria-Hungary had taken over Bosnia, a region next to Serbia. Some of those who lived in Bosnia were Serbs and wanted to be part of Serbia. The Black Hand was an organization that agreed with the idea and sent men to kill Archduke Franz Ferdinand of Austria while he was visiting Sarajevo, the capital of Bosnia. All of them failed to kill him with grenades while he passed through a large crowd. However, one of them, a Serbian student, Gavrilo Princip, shot him and his pregnant wife with a pistol.