The supplementary information provided in this QR-code accessed section takes the form of a series of questions that you may have about the ‘What and Why?’ section of the exhibition. For more information about the building of the Dyke, you can access the website of the Offa’s Dyke Collaboratory (www.offaswatsdyke.wordpress.com); and you can also access there, on an open access basis, all the articles published in the volumes of the Offa’s Dyke Journal. The ODJ is a periodical (annual) publication that carries peer-reviewed articles not only on the Early Medieval frontier between England and Wales, but also papers that discuss the history and archaeology of historic boundaries elsewhere in Britain, Ireland, continental Europe and beyond.
You can also read in some depth about the Dyke and the historical context of its construction in the book Offa’s Dyke: Landscape and Hegemony in Eighth-Century Britain by Keith Ray and Ian Bapty (Windgather Press, 2016; reprinted 2019). A new book by Keith Ray, Offa’s Dyke: Encounters and Explanations, which will serve not only as an introduction to current thinking but also as a detailed field guide to the monument, will be available during 2022.
Panel 3 Offa’s Dyke: a linear earthwork
- What was Offa’s Dyke?
Offa’s Dyke is most simply thought of as ‘a continuous bank and ditch with the ditch on the western side of the bank so that the linear earthwork faces west into Wales.’ However, this apparent simplicity is deceptive. The Dyke was in fact a highly engineered and sophisticated structure, the siting of which in the landscape had been carefully surveyed in advance of construction. Moreover, its form was designed to achieve a systematic series of effects including the reduction of likelihood of collapse on steep slopes and the avoidance of visual diminution on slopes by minimising the impact of perspective over distance.
- What was the Dyke designed to do?
The Dyke is thought to have achieved two things, primarily. Firstly, it helped define the western frontier of Mercia in contrast to the zones of influence of the various Welsh kingdoms and princedoms of the Cambrian uplands and valleys to the west. In this regard its exact location (mostly on westwards-facing slopes from which it often dominated the landscape westwards) and its built design (massive in-depth ramparts, deep ditch and stone-capped bank, built to echo earlier Roman – and often stone-built – walls of the northern British frontier) reinforced this sense of coercive power. Secondly, it served as a marker of Mercian plenipotentiary might within southern Britain. As such it was designed to overawe neighbours to north, south east and west with the military power and organisational strength in depth of Mercia as the hegemonic Anglo-Saxon kingdom of central Britain.
Offa’s Dyke also served to underline the personal dominance of King Offa as the kingly overlord within Britain; and reflected his propaganda (for instance as shown on his coinage) which in effect promoted him as the natural successor to the Roman emperors. The identification of the Dyke with Offa also underlined the notion that the Dyke was in effect his memorial and represented his legacy.
- Why was it built where it was?
The reasons for the choice of the exact line are basically unknown, since there are no surviving documents that explain its purpose. What becomes clear on closer study is that, on the one hand, there is a pattern to its construction (similar siting practices, similar design and build techniques, and so on) such that we can tell we are looking at a single project undertaken within a relatively short span of time. On the other hand, the huge 120-plus mile frontier that it traverses differed from one end to the other. And in fact, there were several different ‘zones’ (culturally, historically, circumstantially) through which it passed. For instance, in the north it is paralleled by Wat’s Dyke to its east an almost constant 3kn away, creating between the two Dykes a kind of ‘neutral zone under Mercian dominance but not necessarily total control.
- What was its relationship to the other long Dyke on the frontier, Wat’s Dyke?
This is dealt with further under Theme 8.