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
SMS Kaiser Karl VI and Argentina. On 25 May, she represented Austria-Hungary at the centennial of Argentina's May Revolution, which won the country's independence from Spain. On 28 June 1914, Archduke Franz Ferdinand, the heir to the Austro-Hungarian throne, was assassinated in Sarajevo; the assassination sparked the July Crisis and ultimately the First World War, which broke out a month later on 28 July. The German battlecruiser , which had been assigned to the Mediterranean Division, sought the protection of the Austro-Hungarian fleet, and so Admiral Anton Haus sent the fleet, including "Kaiser Karl VI", south on 7 August to assist his German ally.