Roman Auxiliary Cohorts

[Rod MacArthur]

Various sources I have viewed seem to show variations as to whether some auxilliary cohorts were Pedites or Equites. It could simply be that some sources are wrong, however I was wondering whether there was any progression in this, ie could Pedites cohorts have arrived in Britain in 43 AD as part of the field army, but later been given a garrison role and become Equites cohorts.

Rod

[M. Demetrius]

Some auxiliary groups were a mix of light infantry and cavalry. So maybe both.

[Rod MacArthur]

Yes, I realise that, but my general impression is that field armies tended to have infantry only auxilliary cohorts plus cavalry alae, whereas mixed cohorts equites were more used in a garrison role. So the question is whether any cohorts, originally infantry only, later received a cavalry detachment.

Rod

[Nathan Ross]

I suppose it's quite possible that a cohors raised as a peditata infantry unit may have had a mounted complement added to it at some point to become equitata, although as auxiliary movements and deployments are such a grey area, depending largely on the snapshots of provincial garrisons listed in the diplomata, it might be difficult to prove this happening. A peditata cohort listed on one diploma may have become an equitata one by the next one - or they may be entirely different units...

But while equitata cohorts did have obvious uses as garrison troops, they were certainly used on campaign too. This can be demonstrated by the few career inscriptions of officers who won decorations for specific campaigns while commanding part-mounted cohorts, e.g:

AE 1951, 00088: praef(ecto) coh(ortis) II Asturum eq(uitatae) / donato bello Brittan(n)ico cor(ona) / murali corona vallari cor(ona) / aurea hasta pura

AE 1951, 00052: praef(ecto) coh(ortis) I Alpinor(um) / equit(atae) donis don(ato) ab Imp(eratore) Caes(are) / Ner(va) Trai(ano) Aug(usto) Ger(manico) Dac(ico) bello Dac(ico)

AE 1994, 01392: praef(ectus) coh(ortis) III Britt(onum) / eq(uitatae) / donis mil(itaribus) hasta pura / vexil(lo) corona mural(i) / ab Imp(eratore) don(atus) voto / susce(pto) in exped(itione) Germani(ca)

And also, very probably, the various cohors equitata recorded as civium romanorum, a distinction presumably won for some deserving exploit.

However, until the mid third century or so, 'field armies' (by which you mean the forces used for specific campaigns, I'm guessing) were drawn from the garrison troops of the nearest provinces, backed up by drafts and detachments from further afield. So while diplomata can give us a useful list of units in a particular place and time, they don't necessarily tell us what those units were being used for.

(The 'field armies' of the Notitia Dignitatum, by the way, are quite different creations to the legions and auxiliaries of the principiate!)

[Rod MacArthur]

Yes, I can see I am going to have to do some more reading.

My real area of expertise is Napoleonic Military History, where I have over 1,000 books on the subject, have written articles and give talks (PowerPoint presentations). I have always had a secondary interest in the Roman era but probably have only 50 books on that period (including perhaps 12 translations of classics, a similar number of Ospreys, and books by Connelly, Webster, several by Goldsworthy, several by Dando-Collins and even one by Boris Johnson).

I am in Spain at present (with a few electronic copies of Roman era books on my laptop) but get back to UK on Thursday (in for a weather shock) when I will be able to look at my hard copy library and see if I can find examples of what I was asking about.

Rod

[Gaius Julius Caesar]

A gent at the RAT conference last year in York did a presentation on Auxillary units throughout the ages, perhaps someone with access to the info he presented might share this, to see if it sheds any light on the question.

[Mark Hygate]

Rod,

Having done quite a lot of research around the subject myself recently (and I must soon think of putting the thoughts down on 'paper' for criticism.. .), I can only recommend some great references that might assist you (if you've not already got them indeed!).

There is the original work by Cheesman (1917) that is available as a scanned download that covers all the auxilia and would give you some useful insight; which has been followed up more recently by the reference tomes of Spaul (Cohors2 & Ala2), which collate all the extant information on each and every auxiliary unit known - including potted history. I referenced them in a local library, as they are not in print and very pricey - but would like them propping up each end of my own bookshelf.

The organisation of the Roman Army and particularly their mounted elements are quite of interest to me just now.....

[Rod MacArthur]

Mark,

Thanks for that. I have a relatively limited amount of information on the Roman era, perhaps 50 books in total, but that includes about 12 Ospreys, which some would not count (although I always think they are good primers, and some quote useful sources and further reading lists). My lists of Auxiliary Cohorts were culled from various internet sources, but I do not know how accurate they are. I will look for Cheesman.

Rod

[Nathan Ross]

I will look for Cheesman.

No need to look far - it's online here!:

Cheesman - The Auxilia of the Roman Imperial Army

:-)

[Rod MacArthur]

Nathan,

Many thanks. Copy downloaded.

It seems that RAT is every bit as friendly and helpful as the Napoleon Series website which I have posted on for many years.

I clearly should have ramped up my interest in Roman Military History earlier.

Rod