The Roman Forts at Caersws

Caersws I – Llwyn-y-Brain

Caersws village stands at the confluence of the Afon Carno with the River Severn in Powys, and was the site of two early Roman forts. The first (Caersws I) was a large fort, perhaps Neronian or even late-Claudian in foundation, sited in a bend of the Severn about ¾ mile to the east of Caersws Village at Llwyn-y-Brain (SO0492). This large campaign fort was replaced in Flavian times by a smaller auxiliary fort lying closer to the river confluence, partly beneath Caersws Village itself; this later fort being designated Caersws II.

Caersws II – Caersws Village

OS National Grid Reference: SO028921
Dimensions: c.590 x 580 ft (c.180 x 177 m)
Area: c.7¾ acres (c.3.18 ha)

Caersws II was first excavated by Bosanquet in the early 20th century but the results were never published. Further excavations were carried out by C. Daniels and B. Jones in 1966 and 1967, who investigated the vicus outside the fort, and sectioned the defences. The recovery from these sections of pre-Flavian pottery including sherds of Samian form 15/17 also of slivers of Flavian polychrome glassware led these excavators to announce that the fort rampart “antedates the work of Frontinus”, which is generally taken to mean that Caersws II was founded by Agricola c.78AD.

The fort is almost a perfect square in outline, with rounded corners and aligned exactly north-south, measuring 580 feet in this dimension by 590 feet east-west (c. ) over the rampart-crests, this defensive bank was fronted on all sides a triple ditch system. The enclosed area is about 7¾ acres (c.3.18 ha), which is quite large for an auxiliary fort, even one housing a five-hundred strong cavalry Ala, and suggests that the garrison was probably a mixed force of auxiliary regiments, perhaps even two or three legionary cohorts, the Roman military elite. It is significant also, that the predecessor of this fort, Caersws I at Llwyn-y-Brain, is also very large, which suggests continuity of the occupying garrison.

Samian tableware recovered from the Caersws II site includes Trajanic, Hadrianic and Antonine specimens. The regimental strong-room in the principia at the centre of the fort was rebuilt in stone sometime during the Severan period (197-211AD), a coin of Septimius Severus was found built within the remains of the fort wall (Simpson, p.83), and the bath-house was perhaps reconstructed c.265. Much of the later history of the fort has been lost, but the latest coins from the site, single specimens of Carausius the Usurper (286-293) and the emperor Constantine (307-337), may indicate continued occupation until the early-fourth century at least.

Classical Evidence for the Roman Forts at Caersws

The classical geographer Claudius Ptolemaeus who wrote in the early-second century attributed a town named Mediolanum to the Ordovices tribe of mid-Wales, and the Latitude/Longitude figures given by Ptolemy firmly locates this town in the centre of Wales, very-likely at or near Caersws in Powys.

Below these [the Parisi in Humberside] are the Brigantes [of northern England] but some distance toward the west are the Ordovices, among whom are the towns: Mediolanum 16*45 56? ¹ and Brannogenium 16*45 56? ²” (Ptolemy’s Geography)

  1. Very likely Caersws in mid-Wales, although another town of this name was also situated in Cheshire (see below).
  2. Ptolemy’s second Ordovician town has been identified as Bravonium/Leintwardine in Hereford & Worcester.

There are, however, two separate references to a town named Mediolanum in the Antonine Itinerary of the late-second century, occurring in the middle of Iter II and as the southern terminus of Iter X, both of which itinera undoubtedly place a town named Mediolanum in the territories of the Cornovii at Whitchurch in Shropshire. This latter town, which lies almost exactly mid-way between the legionary fortresses at Wroxeter and Chester near the Shropshire/Cheshire border should not be confused with the town mentioned by Ptolemy.

All confusion is dispelled when one consults the Ravenna Cosmology produced by a seventh-century monk, which contains two separate but similarly-sounding place-names: Mediomanum (R&C#81) between the entries for Lavobrinta (Forden Gaer, Powys) and Seguntium (Caernarfon, Gwynedd), also Mediolanum (R&C#84) between the Canubium (Caerhun, Gwynedd) entry and the unidentified station Saudonio. All of these towns are listed between the entries for Wroxeter and Chester.

Mediomanum – ‘The Central Fist?’

It is possible that Ptolemy made a small spelling error and himself named the Ordovician town Mediolanum instead of Mediomanum, although this could have been introduced into Ptolemy’s work at some later date by an unknown copyist. However, it is equally valid to argue that the spelling in either the A.I. or R.C. are in error. The name Mediomanum – if we accept the spelling – appears wholly Latin in origin, from the words medius ‘middle, centre’ and manus ‘hand, fist’. The meaning of this place-name “the central fist” has undoubted military overtones, implying that this was the central of (perhaps) three forts in Wales which were held in strength by the Romans; in fact, during the late-2nd century there were indeed, three forts held in strength in Central Wales, Caersws being one, the others being Forden Gaer and Castell Collen (Todd, p.172).

The intriguing possibility also exists that the second part of this name may have originally been derived from the Archaic Latin word maniple, perhaps implying an early-period legionary presence at Caersws; this is pure speculation, however.

Caer sws – ‘The Camp of Zeus?’

The etymology of the modern Welsh name Caersws is uncertain. The first component of the name is the ancient British word for a fortified encampment, caer, but the second component is the modern Welsh word for ‘kiss’, which is a bit strange, and ‘The encampment of the Kiss’ does not sound right. An alternative suggestion is that the suffix component is derived from the name of the Greek king of the gods, Zeus. It appears possible that Caersws may have been derived from the nominative Caer-Zeus (Pers. Comm. John Davies, resident in Caersws).

References for Mediomanvm?

  • Air Reconnaissance of Southern Britain by J.K. St. Joseph in J.R.S. xliii (1953) pp.81-97;
  • Air Reconnaissance in Britain, 1955-7 by J.K. St. Joseph in J.R.S. xlviii (1958) pp.86-101;
  • Britons and the Roman Army by Dr. Grace Simpson (Gregg, London, 1964);
  • Air Reconnaissance in Britain, 1973-76 by J.K. St. Joseph in J.R.S. lxvii (1977) pp.125-161;
  • Roman Britain 55BC-400AD – The Province Beyond Ocean by Malcolm Todd (Fontana, London, 1981);

Roman Roads near Mediomanvm?

Possible road: NNE (11) to Llanfair Caereinion (Powys) ENE (13) to Forden Gaer (Forden Gaer, Powys) Possible road: SW (15) to Caegaer (Powys)

Sites near Mediomanvm?