Causes of World War I corrective." British Diplomat Arthur Nicolson wrote in May 1914, “Since I have been at the Foreign Office I have not seen such calm waters.” On 28 June 1914, Archduke Franz Ferdinand of Austria, heir presumptive to the Austro-Hungarian throne, and his wife, Sophie, Duchess of Hohenberg, were shot dead, by two gun shots in Sarajevo by Gavrilo Princip, one of a group of six assassins (five Serbs and one Bosniak) coordinated by Danilo Ilić, a Bosnian Serb and a member of the Black Hand secret society. The assassination is significant because it was perceived by Austria-Hungary as an existential challenge
Assassination of Archduke Franz Ferdinand of killing Franz Ferdinand came from a newspaper clipping he received in the mail at the end of March announcing Franz Ferdinand's planned visit to Sarajevo. He then showed the newspaper clipping to Princip and the next day they agreed they would kill Franz Ferdinand. Princip explained to the court he had already read about Franz Ferdinand's upcoming visit in German papers. Princip went on to testify that, at about the time of Easter (19 April), he wrote an allegorical letter to Ilić informing him of the plan to kill Franz Ferdinand. Grabež testified that he and Princip, also at