Gnaea Seia Herennia Sallustia Barbia Orbiana, usually known as Sallustia Orbiana, was a third century Roman empress, with the title of Augusta as the wife of Severus Alexander from AD 225 to 227. The emperor married her in late 225, following the death of his grandmother. Severus was around sixteen years of age at this time. She was known for her beauty, which was captured in multiple works of art. Possibly a victim of the jealousy of Julia Mamaea, the emperor's mother, Orbiana was divorced and exiled to Libya in 227.

Marcus Aurelius Severus Alexander, also known as Alexander Severus, was Roman emperor from 222 until 235. The last emperor from the Severan dynasty, he succeeded his slain cousin Elagabalus in 222, at the age of 13. Alexander himself was eventually assassinated, and his death marked the beginning of the events of the Crisis of the Third Century, which included nearly fifty years of civil war, foreign invasion, and the collapse of the monetary economy.