LAVIUS IOVIANUS) (331-364), Roman emperor from June 363 to February 364, was born in 331. As captain of the imperial bodyguard he accompanied Julian in his Persian expedition; and on the day after that emperor's death Jovian was unexpectedly chosen emperor by the army to succeed him. He at once continued the retreat begun by Julian, and, continually harassed by the Persians, succeeded in reaching the banks of the Tigris, where a humiliating treaty was concluded with the Persian king, Shapur II. (q.v.). Five provinces which had been conquered by Galerius in 298 were surrendered, together with Nisibis and other cities. The Romans also gave up all their interests in the kingdom of Armenia, and abandoned its Christian prince Arsaces to the Persians. During his return to Constantinople Javian was found dead in his bed at Dadastana, halfway between An cyra and Nicaea. Under Jovian, Christianity was established as
the state religion and Athanasius was once more reinstated on the archiepiscopal throne of Alexandria. Paganism, however, seems to have been tolerated. In Syriac literature Jovian became the hero of a Christian romance (G. Hoffmann, Julianus der Abtriin nige, 188o).
See Ammianus Marcellinus, xxv. 5-10 ; Tillemont, Histoire des empereurs, vol. iv.; Gibbon, Decline and Fall, chs. xxiv., xxv.; J. Wordsworth in Smith and Wace's Dictionary of Christian Biography; H. Schiller, Geschichte der romischen Kaiserzeit, vol. ii. (1887) ; A. de Broglie, L'Eglise et l'empire romain an ive siecle (4th ed. 1882) ; Seek, Gesch. des Untergangs der antiken Welt (iv., 338) ; and art. in Pauly Wissowa, Realencyclopadie. For the relations of Rome and Persia see PERSIA: Ancient History.