Placidianus was a Roman general of the 3rd century. He was a
professional soldier who advanced his career under
survived into the age of
Claudius II and Aurelian.
consul in the year 273 as the posterior colleague of Marcus Claudius
Tacitus, the future emperor. His life presented here is largely
derived from L.L. Howe’s history of the Praetorian Prefecture..
There are two inscriptions relating to Placidianus, both from Gaul.
The first dates from 269 in which he is Praefectus Vigilium (i.e.
Prefect of the Roman Watch), but commanding an army detachment against
Gallic Empire and based in southern Gaul and the second is
datable to the early years of Aurelian's rule when he was acting as
Placidianus' nomen, Iulius, may indicate a Gallic origin as many
Gallic families became Roman citizens under the patronage of the
Julio-Claudian Emperors. However, in the two centuries since the death
of the last of the Julio-Caludians,
Nero Julian clans could well have
become much more widely dispersed geographically. His cognomen, i.e.
Placidianus, is not sufficiently common to suggest any geographical
focus for those choosing it. His date of birth is not known.
Similarly, we have no record of him marrying or producing any heirs.
Placidianus is first encountered as Prefect of the Roman Watch - see
Vigiles - under
Claudius II in 269. As Claudius had been so closely
Gallienus it is likely that
Placidianus too had been a
rising star in that Emperor’s entourage. He must, therefore, have
been born with or had acquired equestrian status as
the policy of excluding senators from high commands. Claudius
apparently valued him sufficiently to use him in a very sensitive
That he could be Prefect of the Watch while commanding an army
detachment against the
Gallic Empire (or, most improbably, the Goths)
in southern Gaul supports the notion that high-flying army officers
might be rewarded by appointments to offices in the Roman garrison
while being given more substantive postings elsewhere in the
Whatever mandate Claudius gave
Placidianus when he sent him to Gaul in
Gaul it did not include taking direct action against the 'Gallic
Empire' for it was during Placidianus's watch in the region that the
Victorinus took and sacked the city of Augustodunum
(Autun) which had declared for Claudius without
Placidianus making any
move to relieve it. The most likely explanation for this seemingly
extraordinary betrayal of would-be Gallic supporters of Claudius's
regime by that Emperor's representative in Gaul is that at this time
Claudius was fully engaged either in Italy against the
Alamanni or in
the Balkans against the
Goths and was therefore unwilling to open a
second theatre of operations in the western provinces, which would not
only have involved a major military effort, but would also have
required Claudius to assume responsibility for the defense of the
Rhine frontier had he been successful.
Placidianus is credited by Alaric Watson with
suppressing a potentially dangerous revolt by
Domitianus in the region
south of Lake Geneva in 271. However, the most likely location for
Domitianus's suppression was the Gallic capital, Augusta Treverorum
Placidianus was unlikely to have been operating in 271
so perhaps even this success must be denied him.
Whatever the reason for Placidianus's failure to come to the rescue of
Autun, he obviously made a sufficiently good impression for Claudius's
Aurelian to appoint him his
Praetorian Prefect at or soon
after his accession. It is not known if he directly succeeded Aurelius
Heraclianus who had been Gallienus's last
Praetorian Prefect and had
probably colluded with Claudius and
Aurelian in that Emperor's murder
in 268. It is likely that
Placidianus was still in Gaul when he was
promoted. Howe thinks he remained
Praetorian Prefect until
Nothing is known of
Placidianus after the death of
Aurelian in 275.
^ Alison E. Cooley, The Cambridge Manual of Latin Epigraphy
(Cambridge: University Press, 2012), p. 478
^ Howe, Laurence Lee (1942). The Pretorian Prefect from Commodus to
Diocletian (AD 180-305). Illinois: University of Chicago Press.
^ CIL XII, 2228.
^ CIL XII, 1551.
^ See Kajanto, I. Roman Cognomina, Helsinki, 1965.
^ See Baillie Reynolds, P.K. (1926). The
Vigiles of Imperial Rome.
Oxford University Press, London. In this connection see article
on Lucius Petronius Taurus Volusianus
^ Watson, Alaric (1999).
Aurelian and the Third Century. London:
Titus Flavius Postumius Quietus,
and Tetricus I
Consul of the Roman Empire
with Marcus Claudius Tacitus,