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
Archduke Friedrich, Duke of Teschen of the ruling house, Friedrich adopted a military career, and served creditably for many years as commandant of the V. (Pressburg) Corps. Subsequently, commander-in-chief of the Austrian Landwehr (militia) and army inspector, he became, after the murder of the heir to the throne, Archduke Franz Ferdinand, inspector-general of the Austro-Hungarian Army. In World War I, he was —from the dynastic point of view —as grandson of the victor of Aspern, Archduke Charles, and as nephew of the victor of Custoza, Archduke Albert, the predestined head of the armed forces of Austria-Hungary; and on 11 July 1914 Friedrich was appointed supreme