Hadrian’s Wall is rarely seen as much of a mystery. Even its modern name reveals who ordered this frontier system into being, while a wall is something we can all relate to. As for purpose, the sole Roman statement on the matter has a simple clarity. The Historia Augusta, which was probably compiled more than 200 years after Hadrian’s death in AD 138, records that he ‘was the first to build a wall, 80 miles in length, to separate the barbarians from the Romans’. With the who, what, and why taken care of, there may seem little scope for any real mystery. But one key consideration remains thoroughly enigmatic: what did Hadrian’s Wall do?
As the Wall’s course cut through stable farming communities that were centuries in the making, its likely consequences must also have excited keen interest back when construction started. Even at a conservative estimate, the precise nature of the division that the Roman authorities desired would have determined the future of thousands of people. Much depended on how easy it was to cross the Wall. Frontier gateways within small military posts set at sufficiently regular intervals to coin the name ‘milecastles’ are central to this debate. Although their presence raises the possibility that passageways were provided to minimise inconvenience for local groups, an increasing number of scholars now see these gateways as primarily intended to aid military manoeuvring. If so, major disruption for local people seems certain, but were such groups merely passive recipients of Roman policy? My new book takes a fresh look at the frontier (see ‘Further reading’ box on p.42), arguing that responses by some local communities played an important role in determining the nature of Hadrian’s Wall.
Drawing a line
Clues about what the Wall did can be found in both its design and its interaction with the wider landscape. The Wall’s location on the Tyne–Solway isthmus was presumably largely a consequence of Britain narrowing abruptly there, making a shorter barrier viable. But this region also presents the finest natural east–west corridor north of Stainmore, about 50km away, and south of Tweeddale, roughly 60km distant. The Tyne–Solway passage is created by the valleys of two river systems, which are linked by a 2.55km- wide bottleneck of land known as the Tipalt–Irthing gap. This key junction not only eases east–west movement, but also provides the only place on the isthmus where north–south passage is possible without making a river crossing. As the course of Hadrian’s Wall seals off the lateral east–west valley corridor from the north, it would fit with the Roman authorities paying close attention to the local landscape. The design of the Wall, though, has long been taken to imply that the nuances of the terrain were largely irrelevant to its smooth running.
