Heraclius, my knowledge is more military than civil, though I have done some work on the so-called 'Rise of the Equites' into Senatorial posts under Gallienus.
Also, bear in mind that Roman official terminology - especially during the mid-C3 - is a lot more flexible than modern terminology. So many titles are interchangeable (a bit like 'Commander' and 'General', for instance).
I have given you only the Latin terms. If you need the equivalent Greek ones, just ask.
MILITARY:
praepositus - generic title for 'unit commander'. You can be a praep. coh, praep. alae, praep. vex, or even a praep. leg.
praefectus legionis a.v.l (agens vices legati) - usually used for equestrian legionary commanders, which became more common after the 'reforms' of Gallienus. NB: The changes Gallienus instituted meant that more (but not all) legions came under full equestrian command in the later C3. A.V.L. means 'acting in place of the Legate'.
legatus legionis - non-equestrian (ie. senatorial) legionary commanders.
dux - General: a military commander (usually an equestrian after Gallienus, but by no means always) put in charge of a force of units drawn from multiple provinces - ie. an army. More often than not, these were vexillations rather than full legions, and semi-permanent vexillation seems to have become the norm under Gallienus, most probably out of necessity.
magister exercitus - 'Commander of the army': title given to Iulius Saturninus by Aurelian - BUT the references are all 4th, 5th or 6th Century literary ones, so the title is probably a late-Roman anachronism.
praefectus praetorium - the Praetorian Prefect is still the most senior military figure in the Empire right up to the time of Diocletian and probably beyond.
NB: Diocletian is said to have been the praefectus of the protectors domestici at the time of his accession, but the domestici did not exist until 350 at the earliest, so this is an anachronism of the later Roman sources.
Augustus nostri – our Augustus, or Emperor.
EQUESTRIAN CAREER MILESTONES:
These are titles you can include in the character sheet of an equestrian vir militaris to mark his progression.
evocatus - service in the evocati was a springboard to the centurionate.
centurio protector - a late C3 title which is still debatable, but probably marks you out for better things. Christol is WRONG when he says this is a centurion in the field army, but it takes 10,000 words to explain why. NB: This title does NOT appear until AFTER Gallienus' death.
princeps protector et primipilus - a late C3 title which usually marks you out for promotion. NB: This title does NOT appear until AFTER Gallienus' death.
ex protectoribus - a late C3 title which usually marks you out for promotion. NB: This title does NOT appear until AFTER Gallienus' death.
praefectus castrorum - second-in-command of a legion.
tribunus vigilum/urbiniciani/praetoriae - the urban tres militiae of the career officer, doing his time in the cohorts in Rome.
Tribunus praetoriae prot. Aug. n. (protector Augusti nostri) – a title ONLY found during the reign of Gallienus. Prot. Aug. n. means ‘protector of our Emperor’. It was given to a man who then accelerated through the ranks to very high military office.
Praepositus vexillationem – commander of a detachment of vexillations.
ducenarius - 500 HS man. A property qualification that is a mark of status.
Praefectus legionis avl – Equestrian legionary commander, ‘acting in place of the Legate’.
Praef. Leg. prot. Aug. n. a.v.l. – A title ONLY found during the reign of Gallienus, which marks out the first ever equestrians commanding non-equestrian legions in place of the senatorial Legate.
NB: The 3 Legg. Parthicae and II Traiana in Egypt were always commanded by equestrian praefecti (I believe that’s true of the 2 Legg. Italicae also, but I’m not absolutely sure).
vir egregius – a mark of status which sets you up for provincial command.
Praeses provinciae – Governor of a equestrian province (ie. appointed by the emperor).
vir perfectissimus – a mark of even higher status which is usually coupled with command of a senatorial province.
Praeses provinciae avl – Provincial Governor, appointed in place of the senatorial Legate.
Praefectus Praetoriae – Praetorian Prefect.
Vir consulari ordinari – Ordinary Consul – Petronius Volusianus was made consul after having served as Gallienus’ Praetorian Prefect. He was one of the first viri militares and the model protector Augusti nostri.
EQUESTRIAN CIVIL CURSUS HONORUM
This is the progression of civil posts that an equestrian might go through. Note that very few men ever followed a purely civilian career path.
Advocatus fisci – junior finance officer.
Procurator – financial officer in a province.
Ducenarius
Vir egregius
Praeses provinciae – Governor of an equestrian province (ie. one appointed by the Emperor)
Vir perfectissimus
Praeses provinciae avl – Governor of a province usually governed by a senator.
Praefectus domestici – Prefect of the Household
Vir consulari ordinari – Technically possible, though I believe only Volusianus is attested as such.
SENATORIAL CURSUS HONORUM
It is a fallacy caused by the pro-senatorial bias of Aurelius Victor that Gallienus excluded senators from provincial governorships. I can cite more than a dozen senators who held governorships from and after Gallienus. However, Gallienus DID open certain provinces which had previously been exclusively senatorial, such as Arabia and the Pannonias, to equestrians during his reign.
Tribunus militum – The last 2 known tribuni laticlavii date from the reigns of Decius and Gallienus. Both were children. So it is clear that by this point, the post had become a sinecure.
Aedile – city administrator in Rome. It still holds a certain cachet.
Praetor – junior magistrate in Rome.
Tibunis cohortis or alae – unit commander
Praepositus vexillationis – Vexillation commander. I don’t actually know of any senatorial praep. vexx. but that doesn’t mean they didn’t exist.
Legatus legionis – legion commander.
Consul – Consul in Rome.
Vir clarissimus – ex-consul.
Legatus or praeses provinciae – Provincial governor. Also labelled v(ir). c(larissimus). leg(atus). Aug(usti). p(ro). pr(aetoriae). Governors of ‘senatorial’ provinces were technically appointed by the Senate.
Dux – army commander.
I think that’s probably enough. If you need a list of the senatorial and equestrian provinces, and dates when they changed, just let me know.
M<