Illustres, the Latin name given to the highest magistrates of the later Roman Empire. The designation was at first informal, and not strictly differentiated from other marks of honour. From the time of Valentinian I. it became an official title of the consuls, the chief praefecti or ministers, and of the commanders-in-chief of the army. Its usage was eventually extended to lower grades of the imperial service, and to pensionaries from the order of the spectabiles. The Illustres were privileged to be tried in criminal cases by none but the emperor or his deputy, and to delegate procuratores to represent them in the courts.
See O. Hirschfeld in Sitzungsberichte der Berliner Akademie (1901), p. 594 sqq.; and T. Hodgkin, Italy and her Invaders (Oxford, 1892), i. 603-617.
