Serbian Campaign of World War I Serbia, Montenegro, and Greece. When Bulgaria attacked both Serbia and Greece on 16 June 1913, it lost most of its Macedonian region to those countries, and additionally the Southern Dobruja region to Romania and Adrianople (the present-day city of Edirne) to Turkey in the 33-day Second Balkan War, which further destabilized the region. On 28 June 1914, Gavrilo Princip, a Bosnian Serb student and member of a multi-ethnic organisation of national revolutionaries called Young Bosnia, assassinated Archduke Franz Ferdinand of Austria, the heir to the Austro-Hungarian throne, in Sarajevo, Bosnia. The political objective of the assassination was the independence of
Assassination of Archduke Franz Ferdinand café with the words 'Mehmedbašić who to-morrow is to be with us.'" The three sent a postcard to Black Hand Provincial Director for Bosnia-Herzegovina Vladimir Gaćinović in France. The following morning, on 28 June 1914, Ilić positioned the six assassins along the motorcade route. Ilić walked the street, exhorting the assassins to bravery. On the morning of 28 June 1914, Franz Ferdinand and his party proceeded by train from Ilidža Spa to Sarajevo. Governor Oskar Potiorek met the party at Sarajevo station. Six automobiles were waiting. By mistake, three local police officers got into the first car with the chief