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
Archduke Franz Ferdinand of Austria Franz Ferdinand's death, with Austria-Hungary's declaration of war against Serbia. The assassination of Ferdinand is considered the most immediate cause of World War I. Franz Ferdinand is interred with his wife Sophie in Artstetten Castle, Austria. Archduke Franz Ferdinand and his Castle of Artstetten were selected as a main motif for the Austrian 10 euro The Castle of Artstetten commemorative coin, minted on 13 October 2004. The reverse shows the entrance to the crypt of the Hohenberg family. There are two portraits below, showing Archduke Franz Ferdinand and his wife Sophie, Duchess of Hohenberg. The Scottish band Franz Ferdinand named