Roman emperor ad 222–35. Son of Julia Avita Mamaea by her second husband, the procurator Gessius Marcianus of Arca Caesarea in Syria, b. c.ad 209, his names were Gessius Alexianus Bassianus until his adoption in 221 by his cousin Elagabalus, when he became Marcus Aurelius Alexander Caesar. Made emperor on Elagabalus' murder in March 222, he took the further name Severus and was called ‘son of the deified Antoninus’ (Caracalla). His mother, under whose influence he remained throughout his reign, set out to recreate a ‘senatorial regime’, with a council of sixteen. Elderly senators such as Marius Maximus and Cassius Dio were prominent. The jurist Ulpian became praetorian prefect but, at latest in early 224, was killed by the guard; Dio was obliged to hold his second consulship (229) outside Rome to avoid the same fate and expressed concern at growing military indiscipline at the end of his History (bk. 80). Alexander was married in late 225 to Gnaia Seia Herennia Sallustia Orba Barbia Orbiana Augusta, whose father may even have been made Caesar; but she was banished two years later when her father attempted a coup. A major new threat resulted from the collapse of Parthia and the revival of Persia under the Sasanids, c.224–5. In 231 Alexander launched a Persian expedition. The war, in which he took only a nominal part, ended in 233; although not a great success, it maintained Roman control over the province of Mesopotamia. Meanwhile the Alamanni were threatening Upper Germany and Raetia. A further expedition was necessary. Alexander wintered in Germany in 234–5, but before the campaign could begin was murdered outside Mainz, with his mother, in an uprising led by the equestrian commander Gaius Julius Verus Maximinus (February or March 235). His memory was condemned, but he was deified in 238 after Maximinus' death.
Anthony R. Birley
Subjects: Classical Studies.