Zodiac and Late Roman Army Organisation

[Nathan Ross]

There was also another term, can't remember though but I think it started with a P and it meant command over the limitanei garrisons.

Are you thinking of praepositus limitis, perhaps?

There's also praeses - this was an equestrian governor from the mid third century onwards. There's some evidence that (at least under the tetrarchy) they were still commanding troops - an inscription to Aurelius Arpagius, praeses of Britannia Secunda under Constantius, on Hadrian's Wall.

Shortly afterwards, command of limitanei garrisons was given to the regional Dux and separated completely from civil control. Individual limitaei legions were commanded by the praefectus legionis, as mentioned above.