Heraclianus's later association with Claudius Gothicus and Aurelian in the assassination of Gallienus - see below - also suggests that he had connections with the Illyrian clans that dominated the officer cadres of the Balkan garrisons in the 3rd century AD.
Heraclianus was thus likely to have been a highly competent soldier who was either born into the Illyrian military élite or earned a place in their ranks by his behaviour in Gallienus's many wars against barbarian invaders and would-be usurpers.
This is the only ancient reference to such an attempt being made in Gallienus's reign and the usual caveat regarding the reliability of the Historia Augusta as a historical record must apply.
[8] Alföldi suggests that Gallienus may have attempted to assert his authority in Asia if not in Syria and Mesopotamia after the death of Odenathus (vis-a-vis Palmyra not Persia), but the effort was negated by the barbarian invasions of the eastern Balkans of the final year of his reign.
However, Prof. Potter does make the interesting suggestion that Heraclianus might have made an expedition to the East to reassert Roman authority in the Asian provinces not in 267 - when he was almost certainly engaged in the Gothic war - but at the behest of Gallienus's murderer and successor, the Emperor Claudius Gothicus, in 270.
Heraclianus appears in the Historia Augusta (Vita Gallieni), Zonaras and Zosimus, but it is impossible to develop any sustained narrative of his life from the ancient sources.
The references are usefully listed by L. L. Howe in his book on the 3rd century Praetorian Prefect: The best recent summary of the available information on Heraclianus is to be found in John Bray's biography of Gallienus: See also: