Greater Serbia the Kingdom of Serbia retreated from Durrës in April 1913 under pressure of the naval fleet of Great Powers, but it remained in other parts of Albania for the next two months. The secret military society called Unity or Death, popularly known as the Black Hand, headed by Serbian colonel Dragutin Dimitrijević Apis, which took an active and militant stance on the issue of a Greater Serbian state. This organization is believed to have been responsible for numerous atrocities following the Balkan Wars in 1913. In 1914, Young Bosnia member Gavrilo Princip assassinated Archduke Franz Ferdinand in Sarajevo, which set
Assassination of Archduke Franz Ferdinand mobilized. Russia's mobilization set off full Austro-Hungarian and German mobilizations. Soon all the Great Powers except Italy had chosen sides and gone to war. Later, referring to Franz Ferdinand's assassination, Vaso Čubrilović said: "We destroyed a beautiful world that was lost forever due to the war that followed." Various countries of the former Yugoslavia, Bosniaks and Croats largely view Gavrilo Princip as a terrorist and an ethnic Serb nationalist. The 100th anniversary of the assassination was commemorated with a concert by the Vienna Philharmonic in the Sarajevo City Hall, in an event that was organized by the European Union. Austrian