I just watched Episode 3 of Michael Wood’s 1981 documentary series, In Search of the Dark Ages, ‘In Search of Offa’. This series is an interesting concept — Wood does not popularise history through dramatic re-enactments or even retelling many of the stories associated with the person and time under discussion. Instead, he engages the viewer with a combination of retelling select episodes and many visits and combinations with long-haired, bell-bottomed archaeologists, many of whom are also very well-bearded. The story, then, is told through archaeology.
The most significant archaeological site associated with Offa is not a then-recently-discovered 6-foot-long, 2-foot-high piece of defensive wall in Hereford (‘very interesting’, ‘the most extensive piece of Anglo-Saxon defensive wall found in the whole of the British Isles’), but, of course, the dyke.
Offa’s Dyke is a big … dyke … separating the land controlled by this powerful Mercian king and the land of the Welsh. It was 64 miles long, consisting of (and here I quote my Encyclopedia of the Anglo-Saxon World) ‘an earthen bank thirty feet (10 m) wide with a ditch six feet (2 m) deep and twelve feet wide (4 m) on the Welsh side.’
In the documentary, the archaeologist with whom Wood is discussing the dyke says that he thinks the dyke was purely defensive. The gates postulated by Fox in the 1930s proved to be later modifications of the original construction. Unlike Hadrian’s Wall and the Antonine Wall, there were no points of controlled crossing between one domain and the other. The Welsh were to be kept out. Or at least deterred. Not controlled.
This is all well and good.
However, the archaeologist then proceeded to imagine a palisade atop the dyke, possibly even with towers. And a garrison. My Encyclopedia says that no evidence of a palisade or a fortress has been found in 71 (!) excavations of Offa’s Dyke.
My immediate reaction was to question this reconstruction — current thinking doesn’t even tend to put a palisade on the Antonine Wall (my post on that here), and it’s not as long (37 miles). Furthermore, the idea of armies watching for Welsh raiders and using signal outposts to call up all the locals for a skirmish — this implies a standing army somewhere other than the kings’ warbands.
A garrison just sitting around on a fortification like that with nothing to do but keep out cattle-rustlers requires a sophisticated system of taxation and provisioning, as well as a professional army, the likes of which I don’t believe King Offa would have had. He was a conqueror — his kingdom was so large and united because he kept killing off other dudes. Not because of marriage alliances or inheritances. Not because he had a long tradition of complicated tax-raising such as Rome had had.
Nonetheless, my Encyclopedia does verify the essentially defensive nature of the dyke. Even without a standing army, a fortification such as this without a single gate would have proven an obstacle to raiding parties. Even if its deep is not as deep as that of the Antonine Wall — 2m vs 6 m — it is an impressive deterrent. And this is part of the function of both the Antonine and Hadrian’s Walls — part of controlling movement is keeping out the movement you’d rather not have.
So, even if Offa’s Dyke may not have had a standing army, it is still a wondrous piece of military engineering. Well done, Offa of Mercia, one of the few kings Charlemagne considered nearly his equal.