The Dacians: Rome\'s Greatest Enemy?

[Frostwulf]

It is. If we can assume an equal number of auxiliaries (not certain, but a good bet), then the force could number 20,000. No paltry number of men.

Besides, a provincial governor, in normal circumstances, could only command the legions based in his own province. Oppius Sabinus ruled a united Moesia, so had four legions at his disposal - but he was surprised by a raid across the Danube and would probably only have been able to summon two of them at most to meet the threat.

So, presumably, the emperor went back to the Danube c. August 86. Immediately, he divided the province into two, retaining Cornelius Nigrinus in Lower Moesia (to the east) and, for Upper Moesia (to the west), moving L. Funisulanus Vettonianus from Pannonia. pg.141

Most authors represent the measure as an immediate response to the invasion, rather than a considered precation put into effect before the Dacian crossed the river. The division may have been put into effect in 84/85, or 85/6. Strobel and others date the creation of the two provinces to 86, as part of the reorganization after the disastrous loss of Fuscus and his army but there is no firm dating evidence. pg.94

Regardless it seems that according to what I have read it was 2 legions used. Blanchard says Sabinus left with a collection of auxiliaries, which to me denotes nothing large or equaling of the legionnaires numbers. This being the case we have to remember some were left behind for garrison and other duties.

Cf.J.C. Mann, Legionarry Recruitment and Veteran Settlement During the Principate (1983), 54-5. Even in times of peace, a legion with a nominal strength of 5,000 could expect to lose an average of 200 ment per year through the expiration of their period of service, while as much as 66 per cent of any army unit could be unavailable for duty at any one time because of illness, detached duties, and the liek: J. Bennett, "The Setting, Development and Function of the Hadrianic Frontier in Britain' (1990), 91 and 486-7. pg.232

As to the exact number, just like in most of these cases its up to interpretation,Strobel tends to max out his numbers and Blancard tries to make educated guesses.

Fuscus, as an equestrian, was officially not permitted to lead legions at all! Quite possibly his army was made up of vexillations of a number of different legions supported by praetorian cohorts. Alternatively, given a special command, he could have led the two legions of Moesia Superior with detachments of others. Tettius Julianus was governor of the (divided) Moesia Superior, so had two legions - but his army, again, probably included strong detachments of others.

If these seem small, it's worth comparing them to other attested non-imperial field forces of the period (attested in sources, that is, not modern conjecture): Varus in Germany in AD9 had 3 legions, Germanicus had 4 (although 8 at his final battle), Plautius invaded Britain with 4, Corbulo had 3 plus a vexillation in Armenia in AD58, Paulinus had 1 plus a vexillation against Boudica in AD61, Vespasian had 4 in Judea, Paetus led 2 into Armenia, Agricola led a maximum of 4 into north Britain (although he only had c.20,000 men with him at the final battle), Arrian planned to lead 2 against the Alans, and so on. 2-4 legions appears to have been quite the norm for provincial offensive operations. If the emperor himself was in charge, of course, the number could increase - but few reliable sources I can find mention more than 8-10 legions total.

As you seem to point out it is all relative. For me I'm not a professional, nor do I have time to dig into all the related sources, therefore I rely on them. When there tends to be a consensus(unless something stands out) I tend to go with what they say. Again you have made some excellent points, thank you.