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Military Sites of Roman Britain

The military occupation of Britain by the Romans is one of the most visible aspects of archaeology in the United Kingdom. After two aborted attempts at invasion, lead by Julius Caesar in 55 and 54 BC, the third occasion, prompted by the Emperor Claudius in AD 43 resulted in 365 years of Roman rule, with traces still present to this day, and can therefore be described as an unmitigated success.

The initial invasion, conquest and subjugation of the local inhabitants was, by necessity, through force and it has been estimated that around 50 000 men were part of the invasion force. The various tribal factions responded differently to the coming of the Romans and there were incidences of rebellion and unrest for a considerable period. Over the next 90 years, although force remained an essential mechanism it was also possible to use other methods, particularly in order to maintain control after conquest. This included bribes and goodwill, taxation, demonstrations of status and power, installing Roman allied settlers and so forth.

The evidence for the military occupation and activity in Britain comes from both documentary sources and archaeological remains. The two elements are not always exclusive, as the writing on the wooden tablets recovered archaeologically at Vindolanda, demonstrate. The body of evidence also includes place-names and the presence of Roman forts can sometimes be attested by the names: -chester, -caster and -cester, the name being a derivation castra, a Latin term for military camp of fort.

Roman Army

Four legions are known to have been part of the initial invasion force in 43 AD. A legion (approximately 5000 men) consisted of ten cohorts. A cohort (480 men) was made up of six centuries, each of 80 men. The men in the legion comprised mostly infantry but a cavalry unit was also attached to them. The soldiers were required to serve for 25 years before they could retire. In addition to these Roman soldiers there were also auxiliary troops that had been recruited from the indigenous populations of the various provinces of the Roman Empire.

The presence of the large military force resulted in numerous structures being built in order to serve the logistics of the Roman army. This primarily includes; forts, milecastles, roads and town walls. Roman Forts

There are different types of forts with the main differences being size and construction materials. The majority conform to the same basic layout, which allowed a well practised method of setup to be developed by the Roman army. This was already part of their system when the occupation of Britain took place. There are hundreds of known sites but new discoveries are being made regularly, adding to the corpus of knowledge and extending the picture of Roman Britain.

The classic Roman fort was rectangular with rounded corners, usually termed 'playing card' shaped. The perimeters were formed by a system of banks/ramparts and ditches, the banks being created by the digging of the ditches themselves, meaning that materials did not have to be transported for the construction of the most basic fort. Timber would be utilised from the surrounding landscape for palisades, which were timber walls along the top of the banks.

Within the circuit of defences the interior would be laid out with roads at right angles to each other with a central gate in each side controlling access to the fort. The central area would have seen the construction of the headquarters building (principia). This housed the main offices, the treasury, and possibly a shrine. In most forts there would also have been; storehouses, granaries, barracks for the troops, stables for the cavalry horses and pack animals; wagon sheds, workshops, a hospital area, senior officers quarters and bakehouses/ovens, although these had to be carefully placed due to fire risks. Perhaps for the same reason the accompanying bathhouses were positioned outside the fort perimeters. Parade grounds would be located both within and outside the forts and areas for practising and developing fitness and fighting skills would have been an integral element of the forts.

The forts and their occupants were not a sedentary setup, there would have been frequent changes in staff, locations and the nature of the forts themselves. Many were rebuilt in stone after their initial construction and the military process of occupying Britain was ongoing and varied over the four centuries.

Temporary forts: would have probably been set up for short durations such as overnight encampment in hostile territories. Out of expediency these would have been built of soil and timber.

Forts: there are over 125 known forts, many were located for strategic reasons, such as; to protect river crossings and ports; provide defensive positions; position troops near or in local communities; assert control over new territories; and form part of a cohesive network providing easy and access to military support. The forts would also have been part of the overall control of the country alongside the towns, and assisted in aspects such as collecting taxes. They also provided homes for the garrison men and their existence meant a focus of activity and settlement for any associated travellers, soldiers’ families and tradesmen and in addition their presence may have spurred the local economy. Evidence for this can be demonstrated through the presence of civilian settlements that became established next to forts, known as vici. Hardknott fort in Cumbria is probably the highest fort in the Roman Empire.

Examples of the numerous forts are to be found at; Reculver, Kent; Brancaster, Norfolk; Cardiff; Cullompton, Devon; Caernarfon, N. Wales; Manchester, Lancaster, Catterick, N. Yorkshire; Ravenglass, Cumbria; as well as Housesteads, Vindolanda and Chesters on Hadrian's wall.

Milecastles: These were positioned between forts along frontiers and there is an extensive network of them along Hadrian's Wall and others are thought to be located in association with other frontier areas.

Fortresses: these would have been larger bases of perhaps 20 hectares (50 acres). There were three permanent legionary bases in Roman Britain:- Caerleon, Chester and York. The most northerly legionary fortress known in the Roman Empire is at Inchtuthill, west of Dundee.

Caerleon (Isca Silurium) : Gwent This was one of the three permanent legionary bases in Britain, occupied by the Legio II Augusta from AD 74 through to the end of the Roman occupation. The exceptional element at Caerleon is the amphitheatre, completed around AD 80 it has been fully excavated. The majority of the remains visible here relate to the legionary fortress and include; well preserved ovens built into the western ramparts of the fort, barracks and communal latrine.

Chester (Deva) : Cheshire. This was one of the three permanent legionary bases in Britain, occupied from AD 76 through to the end of the Roman occupation. This fortress was the main control centre for North Wales and the Pennines. The original timber fort was replaced in the second century by a stone one and there is excellent preservation of the Roman defensive walls. The remains uncovered here include; the principia, legionary offices, legionary bath block and the impressive amphitheatre, the last has been subject to recent work by English Heritage as part of the Chester Amphitheatre Project ( There has also been evidence of the Roman quays along the River Dee, which is one of the elements that made Chester such a place of importance.

York (Eboracum) : North Yorkshire. This was possibly the earliest of the three permanent legionary bases founded sometime after AD 70, and established to provide a secure North-eastern base on the River Ouse. In the third century this became the capital of the subdivided province of Britannia Inferior. The best surviving remains are the third century defences built by the Emperor Constantius. They include sections of walls, gates and towers. There is also abundant evidence of street layouts, a bath house and the principia lies beneath York Minster. The substantial excavation work, which has occurred in the city since the 1970s, revealed good preservation of organic remains in waterlogged conditions; enabling details of everyday life to be seen.