Offa's Dyke

Coordinates: 52°20′38″N 3°02′56″W / 52.344°N 3.049°W / 52.344; -3.049

Schematic cross-section of Offa's Dyke, showing how it was designed to protect Mercia against attacks/raids from Powys.

Offa's Dyke (Welsh: Clawdd Offa) is a massive linear earthwork, roughly following some of the current border between England and Wales. In places, it is up to 65 feet (20 m) wide (including its flanking ditch) and 8 feet (2.5 m) high. In the 8th century it formed some kind of delineation between the Anglian kingdom of Mercia and the Welsh kingdom of Powys. It has been the subject of considerable research in recent years, dispelling many of the earlier understandings.

Overview

A section of Offa's Dyke

It is generally accepted that much of the earthwork can be attributed to Offa, King of Mercia from 757 to 796. Its structure is not that of a mutual boundary between the Mercians on the one side and the people of Powys on the other. The earthwork was dug with the displaced soil piled into a bank on the Mercian (eastern) side. Where the earthwork encounters hills, it goes to the west of them, constantly providing an open view from Mercia into Wales. There is little to no chance that the Dyke was constructed as a defensive earthwork. No army of the period could defend a 120 plus mile long earthwork. It is more likely that the Dyke was constructed as a political statement of power and intent.

Offa was one of the great rulers of Anglo-Saxon times, though his reign is often overlooked owing to a limitation in source material. That he was able to raise a workforce and resources sufficient enough to construct such an earthwork as Offa's Dyke is testament to his power. It is likely that some form of 'service' system along the lines of corvée was used to construct the Dyke, with people from certain areas of land being required to build a certain length of the wall. This can be seen as additional to the normal services that had to be offered to kings. A document exists from around this period known as Tribal Hidage, which makes some assessment of how land was distributed in the 8th century. Though there is little evidence to associate the document with the Dyke, it is possible that both the Dyke and the document stem from a common practice.

Historical evidence

The late 9th- and early 10th-century writer Asser informed us that 'there was in Mercia in fairly recent time a certain vigorous king called Offa, who terrified all the neighbouring kings and provinces around him, and who had a great dyke built between Wales and Mercia from sea to sea' (Asser, Life of Alfred, 14). The last four words are vital: historians and archaeologists coming to the Dyke have had Asser in their hand, looking for an earthwork 'from sea to sea'. Sir Cyril Fox completed the first major survey of the Dyke (Fox 1955), and, in agreement with Asser, saw the Dyke as running from the estuary of the River Dee in the north to the River Wye in the south (approximately 150 miles, or 240 km). It was understood by him that the dyke was not continuous, being built only in areas where natural barriers did not already exist.

Map of the British isles in 802 AD, showing (when enlarged) Offa's Dyke between Mercia and Wales

Frank Stenton, the eminent Anglo-Saxon historian of his day, accepted Fox's description, and wrote the introduction to Fox's account of the Dyke. Though Fox's work has now been to some extent revised, it remains a vital record of how stretches of the Dyke that are now destroyed, still existed between 1926 and 1928, when his three field surveys took place.

Modern scholarship

Frank Noble did much to challenge Fox's legacy. His greatest contribution to Offa's Dyke was to stir up new academic interest. His MPhil thesis, "Offa's Dyke Reviewed" (1978), raised several questions regarding the Dyke. Noble postulated that the gaps in the Dyke were not due to natural features, but that instead a 'ridden boundary' operated, perhaps incorporating palisades that left no archaeological trace. Noble also was vital in establishing the Offa's Dyke Association, which maintains the Offa's Dyke Path, a long distance footpath which mostly follows the route of the dyke, which is one of the designated British National Trails.

Ongoing research and archaeology on Offa's Dyke has been undertaken for many years by the Extra-Mural department of the University of Manchester. Most recently David Hill and Margaret Worthington have undertaken considerable research on the Dyke. Their work, though far from finished, has demonstrated that there is little evidence for the Dyke stretching from sea to sea. Rather, they claim that it is a shorter structure stretching from Rushock Hill north of the Herefordshire Plain to Llanfynydd, near Mold, Flintshire, some 64 miles (103 km). According to Hill and Worthington, dykes in the far north and south may have different dates, and though they may be connected with Offa's Dyke, there is as yet no compelling evidence behind this. However, not all experts accept this view.^[1]

Alternative theories

The Roman historian Eutropius in his book, Historiae Romanae Breviarium, written around 369AD, mentions the Wall of Severus, a structure built by Septimius Severus who was Roman Emperor between 193 and 211:

Novissimum bellum in Britannia habuit, utque receptas provincias omni securitate muniret, vallum per CXXXIII passuum milia a mari ad mare deduxit. Decessit Eboraci admodum senex, imperii anno sexto decimo, mense tertio. Historiae Romanae Breviarium, viii 19.1
He had his last war in Britain, and to fortify the conquered provinces with all security, he built a wall for 132 miles from sea to sea. He died at York, a reasonably old man, in the sixteenth year and third month of his reign.

This source is conventionally thought to be referring, in error, to either Hadrian's Wall (73 miles (117 km)) or the Antonine Wall (37 miles (60 km)), which were both much shorter and built in the the 2nd century AD.^[2] However, it has been suggested that Eutropius may have been referring instead to the earthwork later called Offa's Dyke.^[3] This theory is rejected by most archaeologists.^[4][5][6]

The Offa's Dyke Centre

Offa's Dyke Centre

The Offa's Dyke Centre is a purpose-built information centre in the town of Knighton, situated on Offa's Dyke on the border between England (Shropshire) and Wales (Powys). Some of the best remains of the 8th-century earthworks can be seen just a two-minute walk from the centre. Additionally, there is a visitor centre at the northernmost point of the walkway in Prestatyn on the North Wales coast.

Cultural references

The Dyke has in some cases been brought into common folklore, though this should not be seen as historical evidence for the purpose behind the Dyke.

Today, the England-Wales border still mostly follows the dyke through the Welsh Marches. It has a cultural significance, symbolising the separation between the two, similar to the symbolism of Hadrian's Wall between England and Scotland in the Scottish Marches.

References

Bibliography

• Cyril Fox, Offa's Dyke: a Field Survey of the Western Frontier Works of Mercia in the Seventh and Eighth Centuries AD, (London, 1955)
• Frank Noble, Offa's Dyke Reviewed, MPhil thesis Open University, (1978). Partly published in Offa's Dyke Reviewed, ed. Margaret Gelling, (Oxford, 1983)
• David Hill and Margaret Worthington, Offa's Dyke: History and Guide, (Stroud, 2003)

On-line

• Offa's Dyke Association website
• Ramblers' Association: Offa's Dyke Path National Trail
• Clwyd-Powys Archaeological Trust: Introducing Offa's Dyke
• How Offa's Dyke created a genetic barrier between the English and the Welsh BBC Gene Stories article

See also

• England and Wales
• Wales-England border
• Wat's Dyke
• Scots' Dike
• Götavirke (Geatish Dyke)
• Danevirke (Danish Dyke)
• Wansdyke
• Separation barrier
• Silesia Walls