<P> The assassination had been carried out by those wishing to unite all of the territories with majority South Slavic population not already ruled by the Kingdom of Serbia or Kingdom of Montenegro . Austria - Hungary's post-assassination ultimatum was part of a coercive program meant to weaken the Kingdom of Serbia's threat to take control of the northern Balkans and its significant Southern Slavic population, especially the Bosnian Serbs . This was intended to be achieved either through diplomacy or by a localized war if the ultimatum were rejected . Austria - Hungary preferred war, though István Tisza, the prime minister of the Hungarian part of Austria - Hungary, hoped that the ultimatum would be reasonable enough that it would not be rejected outright . A month after the assassination of Franz Ferdinand, Austria - Hungary declared war on Serbia on July 28, 1914 . This local conflict ultimately expanded into World War I as more powers became involved . </P> <P> 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 . After Potiorek's suggestion, in summer 1913, that Archduke Franz Ferdinand of Austria, heir presumptive to the Austro - Hungarian throne, might attend military exercises due to be held in Bosnia near the end of June 1914, Emperor Franz Joseph ordered Franz Ferdinand to attend . After the exercises, on 28 June 1914, Franz Ferdinand toured Sarajevo with his wife, Sophie, Duchess of Hohenberg . Six armed irredentists, five Serbs and one Bosnian Muslim, coordinated by Danilo Ilić, lay in wait along Sarajevo's Appel Quay because it was announced that Franz Ferdinand's motorcade would use that route . </P> <P> At 10: 10 a.m., Nedeljko Čabrinović bombed Franz Ferdinand's motorcade as it approached the Čumuria bridge . Twenty people were wounded, but Franz Ferdinand was unhurt . The bomb thrower had been instructed in Belgrade by Serbian Major Voja Tankosić to take potassium cyanide to prevent his capture . Čabrinović swallowed the cyanide, but it only sickened him . The Sarajevo police arrested Čabrinović and brought him to the police first aid post . Investigator Judge Leo Pfeffer was at the police station and was immediately assigned to investigate . Before the investigation got far, news arrived that Gavrilo Princip had shot and killed Franz Ferdinand and Sophie while they were on their way to visit the wounded in the hospital . Princip took his cyanide, but the cyanide had the same effect on Princip as it had on Čabrinović . The police arrested Princip, and he too was brought to the first aid post . Within 45 minutes of the shooting, Princip began telling his story to Pfeffer . </P> <P> By the next day, 29 June 1914, based on the interrogations of the two assassins, Potiorek, Governor of Bosnia - Herzegovina, was able to telegraph to Vienna that Princip and Čabrinović had conspired in Belgrade with Milan Ciganović and others to obtain bombs, revolvers, and money to kill Franz Ferdinand . A police dragnet quickly caught most of the conspirators . Twenty - five people went to trial, but nine were acquitted . </P>

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