AFTER JULIAN: THEMISTIUS ORATIONS 5 AND 6
The period of great personal success inaugurated by Themistius' adlection to the Senate of Constantinople and embassy to Constantius II in Rome was brought to an end by political events beyond his control. In November 355, Constantius had appointed his cousin Julian as Caesar: junior co-emperor in the west. Relations between the two men were never easy, and became progressively more strained when Constantius departed to the east to deal with the military crisis generated by a series of Persian offensives, which had culminated in the sack of the great fortress city of Amida and the destruction of its garrison in 359. Since 357, Julian had enjoyed great success against Alamannic and Frankish tribes on the Rhine, arousing Constantius' jealousy, and used these successes as an excuse for throwing off the control of the advisors with whom Constantius had originally surrounded him. Matters came to a head in winter 359/60 when Constantius demanded some of Julian's troops. Julian's army declared him Augustus, and he rebelled against Constantius, moving swiftly to take over most of the Empire's European territories by winter 360/1. Constantius responded by extricating himself from war with the Persians, preparing a massive counterstrike, and moving westwards. He died, however, on 5 October 361 before war could begin in earnest, leaving Julian as sole emperor.1
Constantius' death did not end the turmoil. Julian apostatised from Christianity, and proceeded to withdraw state support from the religion. In the course of his brief reign, his religious policies hardened, in certain areas at least, into a positive persecution of Christianity.2 Julian was also determined to launch a major war against the Persians, but the policy misfired. After initial successes which took him as far as Ctesiphon, the Persian capital, his army was forced into a long and dangerous retreat back to Roman territory, in the course of which Julian himself was killed
1 On all this, see now Matthews, 1989, ch. 6.
2 See most recently Smith, 1995, ch. 7, esp. 207–18.