Mons Graupius Identified
Addendum: 82 AD
What happened in 82 AD and where?
82 AD
Now that we have identified the scene where campaigning in 83 AD and the location of the great battle itself took place, it is understandable that many will now wish to identify the location of the events of 82 AD, Agricola’s penultimate year of campaigning and the scene of the Caledonian assault on the marching camp of the Ninth Legions battlegroup, as well as understanding better the places and events of the year(s) following 83 AD.
We calculated that Agricola marshalled a force of around 26,000 men in 83 AD for service at Mons Graupius.
It is reasonable to suppose that Agricola – although faced with demands in 82 AD for troops to be dispatched to assist in Domitian’s Chatti war on the continent- will have marched north with broadly similar numbers.
Tacitus has Agricola taking the noteworthy step of recruiting British auxiliaries for his final years campaigning in 83 AD. This may have been a result of a combination of yet a further drain on units being transferred to the continent, but more probably to replace losses in action in 82 AD.
However the events of 82 AD may have persuaded Agricola that additional troops were required to complete the business; for all Tacitus gloss the year ended in a near disaster for the Romans and in 83 AD Agricola will have unlikely marched north to offer pitched battle with fewer troops.
Agricola probably entered Caledonia across the Teith at Doune and while bounding the mountains to his left will have struck north east into lowland Perthshire; Strathallan, Strathearn and Strathmore; "enveloping the tribes" as Tacitus records.
Meanwhile the main fleet harried the east coast, probably sheltering when necessary in the Montrose basin and Stonehaven further north, while ships patrolled the Tay where communications could be maintained with the army while it operated in Strathearn and above the Tay.
Naval units, clearly active in the west out of Vindogara (Irvine) harried the western seaboard, penetrating deep into the landmass up the sea lochs there "opening up the secret places of their (Caledonian) sea".
The eastern coastal lowlands was home to the Venicones and Vacomagi tribes. This was rich agricultural land that would both serve to assist in provisioning Agricola’s forces as well as underscoring his campaign of intimidation through the harrying and destruction that was undoubtedly meted out across it.
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Meantime cavalry vedettes would have penetrated the nearer reaches of the glens entering the highland massif and we can well imagine the depredations that will have been visited on the inhabitants there.
Vacomagi territory lay to the north of the Venicones, their lands probably meeting at the South Esk and it was to the rich lands between the Esks that Agricola was intent on penetrating when cataclysmic word reached him that the cunning Caledonians had slipped past his extended south western flank and assaulted forts to his rear.
The bridgehead fort at Doune – on the fringes of Caledonii territory shows only one phase of occupancy and therefore appears to have weathered the storm.
By 82 AD Agricola had construction put in hand at Ardoch and Strageath, both are forts noted for having two structural phases of occupancy in the Flavian period. It was the unfinished defences of both of these forts therefore - as well as the encampments of the troops employed in building them - that came on the receiving end of Caledonian retribution.
These then are likely to have been the locations where the Caledonian’s action prompted Agricola to change tactic, split his force into 3 separate battlegroups and position them to better control the "routes the Caledonians were using" .
Three large Flavian marching camps are of great interest and their likely capacities is telling.
- Dalginross (near Comrie), positioned to cover Glen Lednock as well as the approaches to the River Earns headwaters at Loch Earn is some 22.25 acres in area, and would accommodate 5,000 men.
- Bochastle (near Callander) covers Strathyre and the route in and out of the Trossachs at Loch Venachar. Here the anticipated threat is countered with a larger force. The camp measured 47.75 acres and is capable of holding a hefty battlegroup of 10,500 men.
- Malling (near Menteith) covers the gap between the Trossachs and Flanders Moss and the threat at this most southerly camp of the three appears to have been sufficient to warrant the 5,800 men bivouacked in the marching camp of 26.4 acres to have been reinforced with a second force of 2,600 men who tacked their smaller 11.6 acre marching camp onto the existing larger camp. This battlegroup now weighed in at a respectable 8,400 men.
The weighting clearly shows the south west was deemed vulnerable and hints that the watersheds from the Trossachs were the routes recently employed by the avenging Caledonians warbands when they stormed the forts in Strathallan.
The Roman force available to Agricola in these three camps therefore would appear to have totalled some 23,900 men. This equates very well with the view that Agricola will have reinforced his numbers for the campaign of 83 AD from that available to him in 82 AD.
The fairly nominal difference between forces effectively 26,000 and 24,000 strong highlights the difficulties Agricola faced raising additional manpower – while making good his losses- when Imperial prerogative was undoubtedly taking priority in drafts of legionary and auxiliary recruits on the continent. This explains his decision to employ British auxiliaries to bolster the thinned ranks of existing auxiliary units.
How did this force arrive at these locations and where were they before this?
Unfortunately, as yet there are no securely identified large Flavian marching camps known in Strathmore that can help identify exactly where Agricola’s large battlegroup ranged ever north-eastwards "enveloping the tribes beyond the Forth" nor how far they reached before developing events caused his abrupt redeployment in the opposite direction - south west.
Interest attends the large camp at Kair House near Laurencekirk. Early analysis of the outline of this camp – visible on aerial photographs- gave proportions of a sub rectangular camp of around 92 acres, an area capable of holding around 20,400 men.
Latterly however a developing understanding of this camps layout has given the unmistakably distinct rectangular proportions of a late Roman marching camp.
It is not outwith the bounds of possibility however that some of the earlier crop mark interpretations may have picked up on the ghostly remains of an earlier use of the site, underlying the later camp.
Later reuse of good encampment locations near large water courses is fairly common. Kair House’s location on high ground above the crossing point of the Bervie Water deep in Vacomagi territory would gel well with the route Agricola would in general terms be most likely to use when heading for the Mounth at Stonehaven.
Kair House is also sufficiently remote from the Trossachs for the Caledonians to strategically exploit the situation and in the process teach Agricola an object lesson on the consequences of over-reaching himself and exposing his extended flanks and supply lines.
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Doubling back to address the problem(s) – Tacitean spin has him "advancing" to meet the threat - Agricola split his forces into three independent battlegroups – each a composite brigade of legionaries with auxiliary units in support - probably somewhere near Innerpeffray.
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Like Kair House the large camp there is from a later period but the general location or its environs on the highly strategic River Earn would be the logical place for Agricola to split his force into three distinct battlegroups to better cover the routes "they (the Caledonian warbands) were using", i.e. those highland glenmouths opening out onto Strathallan and Stirlingshire.
It was at this point -Tacitus tells us - that various nay-sayers in Agricola’s staff corps urged a continued headlong retreat to the Forth Clyde line, something Agricola (at this stage) was not yet prepared to be seen doing while also confirming Agricola had "advanced" nearer to this line, not further away from it.
Located near Innerpeffray is the Flavian camp at Dornock on the banks of the River Earn. At 23 acres it clearly locates the first position of the detached battlegroup of 5,000 men who would then proceed east along the river to the matching sized camp at Dalginross.
A second battlegroup, an almost matching sized contingent of 5,800 men also detached itself from the main body and leaguered up at Malling on the shores of the lake of Menteith in Stirlingshire, reaching there via as yet unknown marching camps.
Agricola’s own column, with staff corps nay-sayers no doubt buzzing around his ears, probably retreated as far south as the marching camp at Dunblane. He would likely have done this in order to assess the effect or indeed extent of Caledonian penetration into lowland Scotland – the "conquered lands" which took Agricola three long hard years to subdue.
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The size of this third camp (32.75 acres, capable of holding 7,300 men) quantifies the number of men in Agricola’s force employed in his northern thrust at some 18,100 men.
This force would require a series of camps in the order of 81.5 acres in size up through Strathmore. Hopefully future investigation of sites like Kair House might bring to light evidence for Agricola’s most northerly penetration of Scotland in 82 AD.
The unaccounted remaining 5,800 men (from the subsequent total of 23,900 we shall discuss presently) was probably an under strength legion with a matching compliment of auxiliaries left guarding the Forth - Clyde isthmus - possibly loitering at Lochlands near Falkirk while Agricola and the main army ranged ever north-eastwards looking for a fight.
It would be a detachment of this force that was engaged building the forts at Ardoch and Strageath (and the roads to link them), and who were attacked by the Caledonians, incensed not least by the navies depredations on the western seaboard but by this physical intrusion on or worryingly near to their lands.
When this force of 5,800 men came up, the archaeological evidence would suggest Agricola split them into two, one group 2,600 strong (perhaps the under strength legion) being sent to reinforce Malling where there must have been threatening signs of Caledonian activity, while the remainder, some 3,200 strong were attached to Agricola’s central powerful column; now 10,500 strong which duly took up station in front of the highland massif at Bochastle (Callander).
Dalginross, Bochastle and Malling would all be locations of continuing concern to Rome, however at this stage there is nothing to suggest Agricola’s troops threw up anything as yet more formidable than marching camps while they actively patrolled looking for signs of Caledonian activity and awaited developments.
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It can be seen that Agricola’s dispositions are heavily weighted to the south of this line, a fact the Caledonians seized on. The most northerly and remote force is that at Dalginross near Comrie. Here then, the battlegroup Tacitus records as being the "weakest" of the three, based around the IX Hispana legion was targeted and assaulted by the Caledonians.
There is compelling evidence to corroborate this.
It is the smallest camp of the three securely datable camps which "control the routes the Caledonians were using", we can well imagine its force of around 5,000 would be a temptingly sized target for the Caledonians who we are told had not yet bound themselves into a larger federation by treaty; that would happen later that winter.
Dalginross sits at a strategic confluence of glens and waterways- the very reason the town of Comrie later evolved there. It is pressed in by the surrounding by hills; a veritable trap.
The "marshes" the retreating Caledonians subsequently sought refuge in can be readily explained by the effects of the confluences of not only the Ruchill Water but also of the River Lednock with the large River Earn, all in an age before land improvement, field drainage and river bank improvements.
General Roy, with a soldier’s eye suggested Dalginross as the scene of this fight and we agree with him.
A Roman fort was located here within a year or two (we do not however agree with Roy’s conclusion that this was the "Victoria" of Ptolemy’s map) and later reoccupation in the Antonine period illustrates the risks the Romans were prepared to continue to take to ensure this problematic hotspot remained closely supervised.
In targeting this weakest battlegroup, located remote from the bulk of Agricola’s remaining forces the Caledonians again displayed considerable strategic skill.
As before they pinpointed the exact position where their stronger opponent had over extended themselves.
On this occasion, either by ruse or luck they appear to have prompted their stronger opponent to strengthen one flank, then attacked and almost succeeded in overrunning the other in one daring night attack. Strictly speaking, they deserved to succeed!
Agricola’s actions on the day also lend weight to this theory.
Once alerted to the Caledonians movements he appears - understandably enough - to have attempted to concentrate his entire force.
Malling is near but not close to Bochastle and Agricola appears to have been forced to dispatch the Bochastle battlegroup alone to Dalginross – an awkward journey around Ben Vorlich - before his column was joined by his troops from Malling.
Tacitus as we should expect attempts to put a positive spin on this, "sending ahead his cavalry and the fastest of his infantry"; in other words the nearest troops; the bulk of the Bochastle garrison while Agricola and his personal escort probably waited for the hard marching Malling garrison to come up.
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The real fighting skill of the northern tribes, not even yet mustered at full strength can now be gleaned.
They had tied down and were in the process of overpowering 5,000 Roman troops in the camp at Dalginross, when as many as 10,500 of the Bochastle garrison men showed up and engaged them.
Yet it was only when the remainder, Mallings 8,400 foot sore force-marched troops showed up and "let out a yell" while their standards "shone" in the rising morning sun that the tribesmen pulled off. The relieving column in other words let it be known that they were arriving. This is not the stuff of drama as Tacitus would have it, this sounds more like drastic tactics upon reaching a beleaguered force in the process of being over-run.
Even while disengaging the tribesmen managed to blockade some of the camps gates and Tacitus is forced to admit that stiff fighting took place there.
This action prevented the survivors of the IXth from following up the tribes withdrawal – indicative that the tribes retreated away from Agricola’s relieving troops and therefore northwards through Comrie and across the various watercourses there - and also prevented turning the withdrawal into the rout that Tacitus clearly wished it had been.
Clearly Tacitus cannot hide the facts, barely disguised by the spin, that the whole affair, for the IXths battlegroup at the very least was a damn near run thing.
While night operations, especially hastily conceived ones are notoriously difficult to execute well, it is clear however that only when – in all probability – all Agricola’s army of nearly 24,000 men were to hand that the Caledonians, probably numbering only a fraction of this number withdrew.
Having well and truly cocked a snook at the might of Rome it is little wonder that Tacitus subsequently recalls how the tribes:
"……..with unbroken spirit they persisted in arming their entire fighting force"
….while Tacitus’s account of the mood of overwhelming joy in the Roman camp at the end of 82 AD remains laughably unrealistic.
It is with this bitter pill swallowed that Agricola withdrew his forces south of the Forth Clyde line in the winter of 82 AD, probably already composing in his head the field report to the Emperor which would justify his actions and minimise the stature of his losses that year.
Given that his army had marched far, yet had not been able to dictate the course of events nor force the Caledonians into pitched battle on grounds and timing of the Romans choice, Agricola would have started to consider long and hard how he would pick up the challenge of successfully overcoming Caledonian resistance the following year.
©2009 Roman Scotland. All Rights Reserved
First Published February 2009
