Fortress of Arad their honor. The most famous prisoner in the fortress of Arad was undoubtedly Gavrilo Princip, who on 28 June 1914 killed the heir to the throne of Austria-Hungary, Archduke Franz Ferdinand and his wife, Sophie, in Sarajevo, which led to the outbreak of World War I. About the inhuman conditions in which prisoners were held in the fortress of Arad warned Ştefan Cicio Pop, deputy of the Romanian National Party in an interpellation to the Hungarian parliament in Budapest during 1917. After the first World War, the fortress was occupied by allied Serbian and French troops under French command, until
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