Offa's Dyke (Welsh: Clawdd Offa) is a large linear earthwork that roughly follows the border between England and Wales. The structure is named after Offa, the Anglo-Saxon king of Mercia from 757 to 796 CE, who is traditionally believed to have ordered its construction, although modern archaeological evidence shows far earlier origins and its original purpose is debated. It delineated the border between Anglian Mercia and the Welsh kingdoms (such as Powys) though a 2014 study indicated a roughly late 6th century date for one part of the dyke (Radiocarbon dates are 430–652 CE with 95% confidence) suggesting Offa expanded existing fortifications. The earthwork, which was up to 65 feet (20 m) wide (including its flanking ditch) and 8 feet (2.4 m) high, traversed low ground, hills and rivers. Today, it is protected as a scheduled monument. Some of its route is followed by the Offa's Dyke Path, a 177-mile (285 km) long-distance footpath that runs between Liverpool Bay in the north and the Severn Estuary in the south. Although the dyke has conventionally been dated to the Early Middle Ages of Anglo-Saxon England, research in recent decades—using techniques such as radiocarbon dating—has challenged the conventional historiography and theories about the earthwork and showed that construction was started in the late 6th century, during the sub-Roman period.
History
Background
The generally accepted theory of the earthwork attributes most of its construction to Offa, king of Mercia from 757 to 796 CE. The structure did not represent a mutually agreed boundary between the Mercians and the Kingdom of Powys. It had a ditch on the Welsh (western) side, with the displaced soil piled into a bank on the Mercian (eastern) side. This suggests that Mercians constructed it as a defensive earthwork, or to demonstrate the power and intent of their kingdom. Throughout its entire length, the dyke provides an uninterrupted view from Mercia into Wales. Where the earthwork encounters hills or high ground, it passes to the west of them. Although historians often overlook Offa's reign because of limitations in source material, he ranks as one of the greatest Anglo-Saxon rulers – as evidenced in his ability to raise the workforce and resources required to construct the dyke. Those requirements were immense – when Michael Wood approached motorway contractors in the late 1970s regarding potential costs in present terms they "threw up their hands in dismay ... impossible, they said." The construction of the earthwork probably involved a corvée system requiring vassals to build certain lengths of the earthwork for Offa in addition to performing their normal services to their king. The Tribal Hidage, a primary document, shows the distribution of land within 8th-century Britain; it shows that peoples were located within specified territories for administration.
Early scholarship
The first historians and archaeologists to examine the dyke compared their conclusions with the late 9th-century writer Asser, who wrote, "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". In 1955, Cyril Fox published the first major survey of the dyke. He concurred with Asser that the earthwork ran "from sea to sea", theorising that the dyke ran from the River Dee estuary in the north to the River Wye in the south: approximately 150 miles (240 km). Although Fox observed that Offa's Dyke was not a continuous linear structure, he concluded that earthworks were raised in only those areas where natural barriers did not already exist. Historian Frank Stenton accepts Fox's conclusions. He wrote the introduction to Fox's account of the dyke. Although Fox's work has now been revised to some extent, it still remains a vital record of some stretches of Offa's Dyke that still existed between 1926 and 1928, when his three field surveys took place, but have since been destroyed.
Later research In 1978, Dr. Frank Noble challenged some of Fox's conclusions, stirring up new academic interest in Offa's Dyke. His thesis entitled "Offa's Dyke Reviewed" (1978) raises several questions concerning the accepted historiography of Offa's Dyke. Noble postulates that the gaps in the Dyke were not the incorporation of natural features as defensive barriers, but instead the gaps were a "ridden boundary", perhaps incorporating palisades, that left no archaeological trace. Noble also helped establish the Offa's Dyke Association, which maintains the Offa's Dyke Path. This long-distance footpath mostly follows the route of the dyke and is a designated British National Trail. John Davies writes of Fox's study: "In the planning of it, there was a degree of consultation with the kings of Powys and Gwent. On the Long Mountain near Trelystan, the dyke veers to the east, leaving the fertile slopes in the hands of the Welsh; near Rhiwabon, it was designed to ensure that Cadell ap Brochwel retained possession of the Fortress of Penygadden." And for Gwent, Offa had the dyke built "on the eastern crest of the gorge, clearly with the intention of recognizing that the River Wye and its traffic belonged to the kingdom of Gwent". Ongoing research and archaeology on Offa's Dyke has been undertaken for many years by the Extra-Mural Department of the University of Manchester. Interviews with Dr. David Hill, broadcast in episode 1 of In Search of the Dark Ages (aired in 1979), show support for Noble's idea. Most recently, 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.
… excerpt ends here. Continue reading the full article.
