Soldiers of the second, sixth and twentieth legions built Hadrian’s Wall. The sixth legion was later based at York and the twentieth legion at Chester. Once built, the Wall’s forts were garrisoned by auxiliary regiments recruited from across the Empire. They included regiments from modern Spain, Romania, Belgium, Syria and North Africa. These regiments were usually around 600 strong, comprising around 480 infantry and 120 cavalry. At any one time many of the soldiers would have been posted away from their forts, on administrative or policing duties.
Auxiliary soldiers were paid, professional soldiers and signed up for 25 years of service. At the end of their service they were granted Roman citizenship and a plot of land. From the third century AD the link between the name of a regiment and its original place of recruitment was weakened. Recruitment was more local, with son following father into the regiment and the units reduced in size.
The Roman military garrison along Hadrian’s Wall has been estimated at around 9,000. Some 15% of the entire Roman army was stationed in Britain, mainly in the north of the province on Hadrian’s Wall, along the Cumbrian coast and along the roads leading to the frontier from the legionary fortresses at York and Chester. This large number of troops can be explained in different ways. It could indicate the importance of the province to the Empire, or the difficulty in keeping native tribes under control. Alternatively, perhaps this was a convenient place to station potentially rebellious troops!
Each fort had a similar layout with barracks, granaries, headquarters, a commander’s house, a hospital, bath house(s) and latrines laid out in a grid pattern. Examples include Birdoswald, Housesteads, Chesters, Vindolanda, Segedunum, Arbeia and Maryport.