Vexillations?

[Duncan Head]

Would we be justified in saying that the legion and auxilia may have been associated, albeit we lack proof positive, and/or that the auxilia are somehow associated with either the legion or the vexillation thereof?
In essence, it comes back to Nicholas' original question: when the vexillation left for wherever it was going, would it have been accompanied by some auxilia as opposed to it and some unrelated auxilia meeting up at the intended destination?  Or are we still unable to say?

I think we are still unable to say for certain; but an association is starting to look a bit more likely.

In this case, II Traiana Fortis was based at Alexandria in Egypt, and its vexillation was operating in Arabia. Did the legion take auxiliaries with it from Alex, or did they come separately? Don't know. However, contrary to what I thought earlier, it does appear that II Traiana shared its fortress base at Nikopolis near Alexandria with at least one auxiliary cavalry unit (two are named in the reference, but I'm not sure if they were present simultaneously). So it's a bit more likely than I originally thought that auxiliaries might have been included in the vexillation, since they do seem to have been more closely associated than in the case of most legions.

[Dangun]

I am finding auxilia quite fascinating.

The body of evidence and the secondary literature for the legions is so intimidatingly vast, I struggle to motivate myself to engage with it. But auxilia are like their shadow, ever-present but less well defined.

[dwkay57]

In Paul Bidwell's "Roman Forts in Britain" English Heritage, he suggests at round about page 31 that the plan of Hod Hill "suggests that it contained a mixed garrison of legionaries and auxiliaries". The next couple of pages then goes on to discuss other mixed or combined garrisons.

Also in Graham Webster's "The Roman Invasion of Britain", when talking about the Plautian frontier he says on page 125 "At this earlier stage in Britain it was evidently the practice to detail legionary cohorts for out-post duties, even sharing a fort with auxiliaries."

Given the age of these books (1997 and 1980 respectively) it is probable that history has moved on and some of the findings / conclusions have been overturned, but a conclusion could be that the Romans grouped forces as required and though not strictly belonging to a legion, auxiliaries may have been close companions for a while.