Antoninus (turncoat)

Antoninus (Greek: Άντονίνoς; Latin: Antoninvs) was a member of the Household Cavalry under Emperor Constantius II, and later a Sassanid advisor to the Shah Shapur II. He played a key role in providing intelligence to the Shah, culminating in the sack of Amida in 359 AD.

Ammianus Marcellinus is the only source on Antoninus:

Ammianus then goes on to describe how Antoninus had been mistreated by the imperial authorities of Constantius II. Having grown tired of losing property and wealth to corruption, Antoninus decided to become turncoat. After contacting the Sassanid authorities, he crossed the Tigris river and joined Sassanids. Antoninus later met Ursicinus in the turn of events leading to the siege of Amida. Ammianus (who was present) noted how Antoninus had come to adopt the dress and customs of the Sassanid court.

There is nothing else known about Antoninus' life, aside from the high position in the court of Shapur II. This may in part have been because he spoke both Greek and Latin.

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