The Mystery of Morbio - Piercebridge

In my first blog, The Northern Frontier, I suggested that at the end of the fourth century northern Britain was protected by a three-layered system of defence. It was the third layer which was of particular interest, as it seemed to be comprised of the sixth legion based at York and three cavalry regiments deployed elsewhere. In this context, the Notitia Dignitatum records that a praefectus equitum catafractariorum was based at a place called Morbio. Until now the location of Morbio has never been satisfactorily established, but if we could determine its whereabouts it would provide us with a much better insight into the strategic thinking of the Roman high command. I previously considered Scaftworth as a potential site and dismissed it on the basis of its size and location. This blog will consider the merits of Piercebridge.

The fort at Piercebridge was constructed on the undulating ground which lies between the Pennine hills to the west and the Tees floodplain to the east. Today, the local landscape is dominated by a mix of arable and pastoral farming, whilst the remains of the fort nestle against the Tees. In the Roman period the North Sea tide probably reached as far as the village of Low Worsall, which is about fifteen miles away, whilst below Piercebridge the river is broad and shallow. These features were probably even more pronounced in the Roman period, although then as now the river would have risen whenever there was any significant rainfall in the Pennine hills.

Piercebridge and its vicus was examined in a number of digs between 1969 and 1981 and a full archaeological report has been published by Cool and Mason. It seems that Piercebridge initially developed as a commercial centre. It lay upon Dere Street and the route to the Wall and it was probably situated at the furthest point inland to which the Tees could be navigated by small craft. The preponderance of glass and broken Samian Ware, which has been found across the site, suggests an element of wealth and wellbeing, whilst beads and personal objects made of bone and jet demonstrate the presence of women and children (Chapter 11 Part 6 P272). To begin with the vicus probably lay at a safe distance behind the frontier, although funerary and dedicatory inscriptions indicate the presence of the army during the Severan period. However, Cool and Mason conclude that the fort probably wasn't constructed until the second half of the third century AD. Frustratingly, only a small proportion of the fort has been excavated due to the presence of the village, but it appears to have been built around what is described as an "earlier courtyard building." This structure is one of the most intriguing aspects of the site.

So, what evidence is there that Piercebridge may be Morbio? In terms of size, at over 4 hectares, the fort covers a much larger area than Scaftworth. Indeed, it is almost twice the size of Chesters and therefore certainly capable of housing a regiment of cavalry. Geographically, the fort is located some forty miles behind the Wall and if called upon a regiment of cataphractarii could probably have marched to Corbridge within two days. To the west of Piercebridge, the upper Tees valley also provides access to the Irish Sea coast and the Roman defences on the far side of the Pennines. Thus, basing a regiment of cataphractarii at Piercebridge does make some strategic and military sense.

Supply would certainly have a been an important factor when deciding where to locate a regiment of cataphractarii, especially if cereals or forage needed to be provided in bulk. Donaghy calculates that a horse weighing 770 lbs, which is unable to supplement its diet through grazing, will require 19 lbs of feed per day. Even where pasture is available, cereals are still required to provide a balanced diet. Thus, in a worse case scenario, a regiment of 350 horse might need three tons of feed per day, the equivalent of six ox carts arriving at the gates each and every morning. In its favour, Piercebridge is located at a place where water and pasture are both readily available. Furthermore, oats and barley may also have been grown locally, reducing the need to transport feed, whether by river or road.

In the 1980's Selkirk interpreted some of the features at Piercebridge as sluices, a dam and a harbour. Such an interpretation supported his hypothesis that in the north of Britain the Romans transported most of their supplies by water, utilising the Tyne, Wear and Tees to access forts in the interior. To provide sufficient depth in the upper reaches, he argued that the Romans introduced a system of dams and weirs to control the flow of water along each river. If this interpretation is correct then the need to move feed by road to Piercebridge would have been greatly reduced.

A number of interesting finds were made during the excavations, including some small pieces of metal plate and studs. These may be the remains of scale or lamellar armour (Chapter 11, Part 1,P1).

It has been argued that the Roman heavy cavalry wore this type of protection. Undoubtedly, the clibanarii who accompanied Constantius upon his triumphal entry into Rome in 357 AD, wore a cuirass of scale or lamellar style armour (Ammianus 16.10.8). Indeed, their spectacular appearance appears to have stolen the show. The image of a Sasanian cataphract from this period is shown below (Encyclopædia Iranica). It is likely that the cavalrymen who accompanied Constantius looked much the same.

Sadly, location and the remains of some scale armour are the only real evidence that these ironclad behemoths may have been based at Piercebridge. Fitzpatrick and Scott refer to a number of burials found in 1855, which included horse skeletons (P115), but these are defined as Anglo-Saxon inhumations. Were they? Unfortunately, no reference or description is given.

Turning to the counter evidence, supply is obviously an important issue. In this context various scholars have tried to use Diocletian's Edict of Prices to calculate the relative efficiency of transporting supplies by sea, river and road. Most agree that water borne transport is much more cost effective than conveying goods by land. However, Anderson has shown that Selkirk's interpretation of the site at Piercebridge is far too ambitious and probably misplaced. He concludes that a system of water management would have been expensive and inefficient, making it much more likely that supplies were transported by road. If so, Piercebridge becomes much less attractive as a site to locate a regiment of cataphractarii.

The significance of the lamellar type armour recovered from the fort is also of doubtful relevance. When discovered it was folded into small bundles, which suggests that the metal was in the process of being recycled. Field walking across the vicus has also recovered significant quantities of slag, which suggests that metalworking was taking place on site. Regrettably, there is no reason to believe that the recovered armour had anything to do with a garrison at the fort. It could easily have been brought to Piercebridge from elsewhere. Furthermore, there is some debate as to whether the Roman cataphractarii actually wore scale armour. In antiquity, the term cataphractus appears to have been used in general parlance to describe all types of heavy cavalry. However, research by modern day scholars suggests that within the Roman army the clibinarii and the cataphractarii had separate and distinct roles. Thus, Eadie argues it was the clinanarii who wore the heavier scale armour, so as to fulfil their function as shock troops. In contrast, the cataphractarii were more lightly armed in a coat of mail (P170), which in tactical terms enhanced both their mobility and durability upon the battlefield. The implication is that the lamellar type armour found at Piercebridge cannot be attributed to the presence of cataphractarii.

At Piercebridge, horse bones have been recovered from the ditches outside the fort and from within the vicus. Although a cataphractus may have been less heavily armoured than a clibinarius, he would still have required a horse capable of carrying his extra weight. As Dixon and Southern point out, this doesn't necessarily mean a horse of greater height but certainly one of greater strength (P172). The expectation is that this should be evident in the archaeological record. Research by Lauwerier & Robeerst, based upon the examination of horse bones found at Roman military sites in the Netherlands, has found that the average height of a Roman cavalry mount was about 14 hands (P277). Analysis of the bones found at Piercebridge indicate an average height at the withers, based upon the metapodials and other bones, of between 13 -13.5 hands (Chapter 12, Part 1, P38). Lauwerier & Robeerst considered such beasts to be native breeds, which means that the bones found at Piercebridge are unlikely to be the remains of cavalry mounts.

Cattle (including oxen), sheep, and pig bones were also found in the inner and outer ditches and in some of the buildings nearest to the fort. No definitive conclusions are made in Cool and Mason's report (Chapter 12, Part 1) as to the scale of the slaughter or the potential volume of meat, leather or wool produced, but the amount was clearly significant. Coins found in the various layers, suggest that the peak periods of activity were during the late third and late fourth centuries, with a hiatus in between (P5). The issue here is whether these animals were slaughtered to sustain a garrison or to provide supplies to the army elsewhere? In this context, a review of the "soldiers brooches" found at the site has found that they cannot be dated earlier than c. AD 75 or later than c. AD 325 (Chapter 11, Part 2, P 189), although it is recognised that such items often materialise in later contexts. This observation suggests that there was no significant military force present at the fort in the late fourth century, at the time when the Notitia Dignitatum was being compiled. Therefore, it seems probable that the slaughter was taking place to supply troops elsewhere.

Another reason to doubt whether the cataphractarii were ever garrisoned at Piercebridge is concealed within the Notitia Dignitatum. The section which lists the forts along the Wall does so in sequence, moving from east to west, which suggests that the record is derived from a route map. Following the same principle in relation to the other forces commanded by the Dux Britanniarum and with York as the starting point, you would expect Morbio to be located somewhere to the south of, or at least beyond Dano, which is believed to be modern day Doncaster. On this basis, Piercebridge lies in the wrong direction and too far to the north to be associated with Morbio.

Finally, there may even be some textual evidence to suggest that Piercebridge isn't Morbio. Vindolanda tablet 670 is a letter from Martius to Victor. It mentions a place called Bremesio, which from the context of the text appears to lie between Corbridge and Catterick. The current edition of the Roman Inscriptions of Britain (RIB) suggests that Bremesio may be Piercebridge, on the grounds that it is the most significant unidentified Roman town between Corbridge and Catterick. To be fair, this assignation is far from certain, and it should be noted that the Antonine Itinerary (Iter I) makes no mention of a Bremesio, which would lie between the entries for Vinovia (Binchester) and Caractoni (Catterick).

So, if it wasn't garrisoned by a regiment of cataphractarii, what was happening at the fort and its environs during the fourth century? The blown glass recovered from the bath house certainly suggests that its facilities were in use (Chapter 10, D.29), whilst fragments from glass vessels and sherds of pottery support the notion of uninterrupted occupation. Perhaps the location of the fort provides a clue. Unlike other forts, such as Corbridge or Binchester, the walls of Piercebridge don't sit upon the main road or dominate its passage, but are set back, so that the vicus lies between the fort and Dere Street. From a military perspective it clearly wasn't seen as important to guard the bridge, which is nearly half a kilometre away. Similarly, the fort doesn't command the main Roman road through Teesdale. This departs from Dere Street to the south of Piercebridge and then runs through Greta Bridge, Bowes and Brough. It would appear that from a military perspective, the fort at Piercebridge wasn't intended to be a key part of the defensive infrastructure.

Although only partly excavated, the internal layout at Piercebridge also seems to be different to most other forts. In this context, it is more akin to the stronghold at Arbeia where a courtyard building was also found in the south-east corner (see below). This residence is presumed to have belonged to the commanding officer and by moving it away from its traditional location on the via principalis, more room would have been created alongside the main entrance to facilitate the movement of transport and goods. Perhaps Piercebridge, like Arbeia, was built to provide a secure supply depot. At Arbeia, grain was unloaded, either for storage or transhipment via the Tyne, to the garrisons along the wall. A similar arrangement may have existed at Piercebridge, only this time it was animals which were being husbanded. The Dales, in what is now the West Riding of Yorkshire, are famous for their sheep, whilst the rich pastures of the northern lowlands are ideal for grazing cattle. The central location of Piercebridge, with regard to the Wall, the North Yorkshire Moors and the Dales, would have made it a convenient place at which to gather and process livestock.

To conclude, until further excavation can take place, the true purpose of the Roman settlement at Piercebridge will remain as another tantalising enigma. On the balance of probabilities, it is more likely that the fort was a supply and support depot, than a base for a regiment of cataphractarii. As such, its use would have been interlinked with the system of local taxation and provincial government. Perhaps Piercebridge was an ideal place at which to herd, count and allocate livestock to the garrisons along the wall; a convenient location at which to establish workshops and industry. In this context it must be remembered that the vicus existed long before the fort and perhaps more information on the activities which took place within the civilian settlement will indicate the true purpose of the site? Did the courtyard building have anything to do with this? Was it an official residence of a governor or provincial administrator? Unfortunately, we can only speculate.


Ammianus Marcellinus; The Later Roman Empire (AD 354 - 378); Penguin Classics 1986.

James Anderson; The Piercebridge Formula in the North-east of England: An Assessment and Alternative Method of Supply to the Roman Army; Newcastle University Library; Thesis L3989.

Antonine Itinerary; Roman Roads Research Association.

British Cavalry Training Manual 1912.

Cool, H.E.M. and Mason D.J.P. (eds). (2008); Roman Piercebridge: Excavations by D.W. Harding and Peter Scott 1969 - 1981; Architectural and Archaeological Society of Durham and Northumberland Research Report 7 (Durham).

Raffaele d’Amato; The Roman Tank of the Eleventh Century; Medieval Warfare, 2012, Vol. 2, No. 6.

Darlington Borough Council: Landscape Character Assessment.

Dawson, Tim (1998); Byzantine and Modern Greek Studies(1998). Kremasmata, Kabadion, Klibanion; some aspects of middle Byzantine military equipment reconsidered.

Karen Dixon and Pat Southern; The Roman Cavalry; Routledge 1997.

Thomas Donaghy; Feeding the Ancient Horse;

John Eadie: The Development of Roman Mailed Cavalry; The Journal of Roman Studies, Vol. 57, No. 1/2 (1967), pp. 161-17.

Keith J Fitzpatrick-Matthews; Britannia in the Ravenna Cosmography - A Reassessment (Revised 2020).

A.P Fitzpatrick and Peter Scott; The Roman Bridge at Piercebridge, North Yorkshire-County Durham; Britannia, Vol. 30 (1999), pp. 111-132.

Flood Information Service.

N. Hodgson and P. T. Bidwell; Auxiliary Barracks in a New Light: Recent Discoveries on Hadrian's Wall; Britannia, 2004, Vol. 35 (2004), pp. 121-157.

Spencer Jones; Scouting for Soldiers: Reconnaissance and the British Cavalry, 1899–1914; War in History, November 2011, Vol. 18, No. 4 pp. 495-513.

Lauwerier & Robeerst: Horses in Roman times in the Netherlands (2001).

David Mason; The Romans in the Tees Valley.

Roman Inscriptions of Britain (RIB); RIB 1022, 1025, 1026, 3253, 3258.

Roman Inscriptions of Britain; Vindolanda inscriptions.

Professor A. Sh. Shahbazi; The Sasanian Army; Encyclopædia Iranica.

C.E. Stevens; Gildas and the Civitates of Britain; The English Historical Review, April 1937, Vol. 52, No. 206, pp. 193-203.

Margaret (Bulmer) Ward; A Summary of the Samian Ware from Excavations at Piercebridge.