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
Emperor of Austria in 1875. As Ferdinand I had no sons, his brother Francis Charles would have become emperor, but was persuaded by his wife to pass over the right of succession to their son, Francis Joseph. He accepted the duty of the Emperor of Austria without having been Crown Prince or "Thronfolger" before. Francis Joseph's only son Rudolf committed suicide in 1889, Francis Joseph's brother Karl Ludwig died in 1896. Karl Ludwig's son Franz Ferdinand became heir presumptive to the throne. He was assassinated in Sarajevo, Bosnia in 1914; due to his morganatic marriage, his son had no rights to the throne.