Europe 260: Thirty Tyrants
The capture of Valerian left Gallienus with the task of defending the entire Roman Empire while it was under attack from all sides. With the emperor unable to be everywhere at once, usurpers sprang up across the empire—‘thirty tyrants’ according to a 4th-century source but more likely around nine over Gallienus’ reign. By September 260 Postumus had seized power in Gaul, Regalianus in Pannonia, and Macrianus and his sons in the East; a fourth ‘tyrant’, Odaenathus, controlled Palmyra but retained nominal loyalty to Rome.
[The map is dated to the dedication of the Augsburg Victory Altar to Postumus, by which point he had extended his control to Raetia and the Macriani were established in the East.]
The rival Roman regime led by Postumus and his successors in Gaul (260–274) is often referred to as the Gallic Empire by modern historians. This term has no real historical basis; identity-wise, the Gallic emperors were simply Roman usurpers who successfully held out in Gaul for 14 years, but lacked the strength to take Rome.
In 260 Regalianus was proclaimed Emperor in Carnuntum, Upper Pannonia, apparently gaining support among both the Moesians and the survivors of Ingenuus’ earlier revolt in Lower Pannonia. To strengthen his position Regalianus elevated his wife, the noble-born Sulpicia Dryantilla, to Empress. He battled the Iazyges, who had been ravaging the region, but was soon undone when his own people aligned with the Roxolani to overthrow him.
260 Revolt of Postumus▲
In early 260 Marcus Cassianius Latinius Postumus led the Rhine legions to victories over the Franks (at Empel, Lower Germania) and the Alemanni (at Augsburg, Raetia). In one or both of these encounters Postumus gained large amounts of booty, which he shared among his troops but not with his nominal commander, Gallienus’ son Salonius. When Salonius’ praetorian prefect Silvanus demanded that Postumus surrender these spoils, the legions rebelled and proclaimed Postumus as Emperor. The unfortunate Salonius and Silvanus were then besieged in Colonia Agrippina (Cologne), betrayed by their own garrison, and executed.
260 Revolt of the Macriani▲
At the time of the Shapur I’s capture of Valerian at Edessa, Valerian’s finance minister Macrianus was nearby at Samosata with the Praetorian prefect Ballista and the imperial treasury. The two led the remaining Roman forces in the area against the Persians and eventually chased them from Asia Minor and Syria. Ballista then urged Macrianus to become emperor, but Macrianus considered himself too old and opted to proclaim his two sons, Macrianus Minor and Quietus, as emperors instead.
260 Rise of Odaenathus▲
When the Macriani declared themselves emperors, they were opposed by Odaenathus, a high-ranking Roman official who ruled Palmyra and had some authority in Syria Phoenice. Unlike the Macriani, Odaenathus refused to proclaim himself Emperor and thereby maintained a nominal allegiance to Gallienus.