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
Archduchess Elisabeth Amalie of Austria Saxony, he had no children. With his second wife Princess Maria Annunciata of Bourbon-Two Sicilies, Karl Ludwig fathered Archduke Franz Ferdinand of Austria, who became heir to the throne of Austria-Hungary, as well as three other siblings. Elisabeth and her older sister Archduchess Maria Annunziata of Austria (later Abbess of the Theresia Convent in the Hradschin, Prague) were the product of his third marriage to Infanta Maria Theresa of Portugal, a daughter of the deposed King Miguel I of Portugal. In addition, her father was a younger brother of Franz Joseph I of Austria, the reigning emperor at the time