Young Bosnia and the Battle of Kosovo. Two notable organizations are referred to in connection with Young Bosnia: Narodna Odbrana and Black Hand. During a Serbian kangaroo court in French-occupied Salonika in 1916–17, Chief of Serbian Military Intelligence Dragutin Dimitrijević Apis testified that he had organized the assassination of Archduke Franz Ferdinand of Austria, in Sarajevo on 28 June 1914, (the assassin was Gavrilo Princip). In the process, he used not only his power over elements of the Serbian military, but also the Black Hand. Leaders of the Black Hand in turn had penetrated Narodna Odbrana and used that organization to infiltrate
World War I 1918 influenza pandemic, which caused between 50 and 100 million deaths worldwide. Military losses were exacerbated by new technological and industrial developments and the tactical stalemate caused by gruelling trench warfare. It was one of the deadliest conflicts in history and precipitated major political changes, including the Revolutions of 1917–1923, in many of the nations involved. Unresolved rivalries at the end of the conflict contributed to the start of World War II about twenty years later. On 28 June 1914, Gavrilo Princip, a Bosnian Serb Yugoslav nationalist, assassinated the Austro-Hungarian heir Archduke Franz Ferdinand in Sarajevo, leading to the July