Procopius: name of a Roman usurper.
Procopius was a distant relative of the emperor Julian the Apostate.note[Zosimus, New History 4.7.1.] During Julian's Persian campaign, Procopius guarded the Upper Tigris valley.note[Zosimus, New History 4.4.2.] When Julian was killed in action (June 363), Procopius (who may have expected to be recognized as emperor himself), recognized Jovian, who had been chosen emperor by the army.note[Zosimus, New History 4.4.3.]
During Jovian's reign, Procopius was living with his relatives in a villa in Caesarea.note[Zosimus, New History 4.4.3.] When Jovian was succeeded by Valens (February 364), Procopius revolted, picking up allies on the Crimeanote[Zosimus, New History 4.5.2.] and finding friends in Constantinople, where a former courtier named Eugenius supported him.note[Zosimus, New History 4.5.2.] However, his armies were defeated at Thyatiranote[Zosimus, New History 4.8.1.] and Nacolaeianote[Zosimus, New History 4.8.3.] and he was executed (366).
The main sources are Ammianus Marcellinus and Zosimus.