Nedeljko Čabrinović not enough to pay for rent and food, let alone books, which, for Čabrinović, were "the only sign of life." In the meantime, he met Gavrilo Princip, and joined the Black Hand in 1912. Two years later, Dragutin Dimitrijević leader of the Black Hand, ordered Čabrinović, Gavrilo Princip and five other conspirators to assassinate Austro-Hungarian Archduke Franz Ferdinand, giving them each a gun and two bombs. On Sunday, 28 June 1914, Archduke Franz Ferdinand of Austria and his wife Sophie, Duchess of Hohenberg were assassinated in Sarajevo by Gavrilo Princip during a visit that had been announced two months prior.
Battle of Kolubara their respective commands, and the 5th and 6th armies were merged into a single 5th Army of 95,000 men. On 28 June 1914, Bosnian Serb student Gavrilo Princip assassinated Archduke Franz Ferdinand of Austria in Sarajevo. The assassination precipitated the July Crisis, which led Austria-Hungary to issue an ultimatum to Serbia on 23 July on suspicion that the assassination had been planned in Belgrade. The Austro-Hungarian government made the ultimatum intentionally unacceptable to Serbia, and it was indeed rejected. The Austro-Hungarians declared war on Serbia on 28 July and that same day the Serbs destroyed all bridges on the Sava