July Crisis reason for armed conflict, the dispute between Serbia and Austria-Hungary over the murdered heir, had already become a sidenote to a general European war. Austria-Hungary had annexed Bosnia and Herzegovina in 1908. Sarajevo was the provincial capital. Oskar Potiorek was the military commander and governor of the province. Emperor Franz Joseph ordered Archduke Franz Ferdinand, heir presumptive to the Austro-Hungarian throne, to attend military exercises due to be held in Bosnia. After the exercises, on 28 June 1914, Ferdinand toured Sarajevo with his wife, Sophie. Six armed irredentists, five Serbs and one Bosnian Muslim, coordinated by Danilo Ilić, lay in
Assassination of Archduke Franz Ferdinand advocate of increased federalism and widely believed to favor trialism, under which Austria-Hungary would be reorganized by combining the Slavic lands within the Austro-Hungarian empire into a third crown. A Slavic kingdom could have been a bulwark against Serb irredentism, and Franz Ferdinand was therefore perceived as a threat by those same irredentists. Princip later stated to the court that preventing Franz Ferdinand's planned reforms was one of his motivations. The day of the assassination, June 28 (June 15 in the Julian calendar), is the feast of St. Vitus. In Serbia, it is called Vidovdan and commemorates the 1389 Battle