Victory title
Victory title (victory over the Medes = Persians), first awarded to Marcus [II 6] Aurelius and Lucius Verus, evidently as the result of a victorious campaign against Media Atropatene in AD 165/6. This title next appears as an epithet for Probus, Diocletian, and his co-rulers, then for Constantine, in each case with the addition maximus. The title has been erroneously ascribed to other rulers.
P. Kneissl, Die Siegestitulatur der römischen Kaiser, 196…