The Purpose of Hadrian's Wall At the beginning of Hadrian's reign there was obviously no peace in Britain. His biographer stated that the Britons could not be kept under control (a victory is indicated by a coin issue from AD 119 with Britannia). Anyway the Trajanic Stanegate system was not efficient enough to keep the native tribes of that area (Brigantes, Selgovae, Novantae) under control. There might even have been an interaction between the Brigantes (within Roman Provincial territory) and the Selgovae (in Lowland Scotland). So the new frontier probably planned by Hadrian himself was the first barrier running over 80 miles from ocean to ocean. The emperor created a really enduring monument of stone to himself maybe even influenced by the Great Wall of China (without evidence). Now we have to discuss the question how this frontier system worked. Although the curtain was built by the legions, it was exclusively manned by auxiliaries and maybe by numeri (irregular units). The forts were big enough to accommodate whole auxiliary units. In Stanwix the biggest fort along the course of the Wall the only milliary cavalry unit of Britain was stationed (Ala Petriana), but it is unlikely that the commander of this garrison was a senior officer of the whole army along Hadrian's Wall. In the central areas infantry cohorts were employed while either flank in the east or west was guarded by cavalry units. There is a debate about the soldiers that were stationed in the milecastles and turrets. Maybe every unit of the forts was in charge of a certain stretch of Wall, but after the original plan there were no forts that could provide soldiers for the milecastles. The suggestion that numeri were employed might be a possibility, but in Britain there is no evidence for such troops in the second century. Most likely there were two or three auxiliary units only with the task to run the milecastles and turrets (suggested by a cohort of Vardulli only mentioned in milecastle 19). Pike Hill Turret Chesters - Bridgeabutement Chesters - Barracks Presumably 8000-10000 soldiers were stationed on a distance of 113 km. So it was not intended to be a defensive boundary, since there were by far not enough soldiers stationed to be able to defend the barrier on any point. It was rather a political and strategical project to protect the province as well as to divide the Roman province from the barbaricum. The milecastles and turrets provided an observation system and the movement through the provincial frontier could be controlled. For civil persons there was probably a very liberal handling suggested at least by the many gates through Hadrian's Wall. The movement in and out of the province was thus closely supervised by the army but allowed. Hadrian's Wall was certainly not a fighting platform. It would be completely contrary to the tactics of the Roman army prefering the wide open terrain, no special weapons were provided and the Wall would have been to narrow. If there were major threats the Roman army would have dealt with it in advance, trying to meet the enemy in the open territories north of the province. Patroulling on top of the wall is still a matter of discussion, at least on the broad Wall it would have been possible but there is simply no evidence yet. So Hadrian's Wall was there to control movement and to discourage raiding parties but individuals were certainly always able to cross the Wall unobserved. The psychological imply for people to the south of the border was the Pax Romana while the hostile tribes of the north should have been impressed by the capability of the Romans building a monument like this. Certainly the Wall was not able to resist a concentrated attack in one point, but it was never intended to be.

The Stanegate The Original Plan The Hadrianic Frontier Modifications