Offa's Dyke

Offa was King of Mercia from 757 to 796 AD. Offa's Dyke is an earthwork rampart that runs from the estuary of the Severn to that of the Dee, along a line that has practically remained the boundary between England and Wales ever since. It consists of a ditch and rampart constructed with the ditch on the Welsh-facing side. Fifteen feet has been given as its greatest height at the present day, a but there is more than one place, this hill, where it reaches at least twenty feet. As originally constructed, it must have been about 27 meters wide and 8 meters from the ditch bottom to the bank top. To stand on the top of the Dyke, at one of these points, is to realize how imposing a barrier it must have been, in the days when the depth of the fosse had not been reduced by the accumulated debris of eleven centuries.

Few historical monuments now existing in the United Kingdom which, for combined extent and antiquity, can rank with the great earthwork called Offa's Dyke. Much of it has been levelled for agricultural purposes, and in various places along its course nearly all traces of it have disappeared. But for long stretches of its length it is in extraordinarily good preservation, and when looked at from neighbouring hills is a striking object in the landscape. That the Dyke itself should have escaped levelling in so many places is less surprising than that the ditch or fosse should still be so unmistakable after the accumulation of the soil and decayed vegetable matter of the intervening centuries. That the fosse must have been originally of great depth is proved by its survival as an easily recognizable - and in many places deep - ditch to this day.

From time to time the theory has been advanced that the Dyke was not built by Offa of Mercia, but was of much earlier construction. The result of archaeological research has now definitely disproved this theory. The mistake has arisen through the presence of Roman remains at certain spots in the Dyke. One discovery of such remains under the line of the Dyke, and below the ground level on which it was raised, is sufficient to prove that its origin is post-Roman. Such a discovery is that of the position of the hypocaust alluded to in the following summing-up of the facts on this point: "It is true that when Offa's Dyke passes a Roman station (as at Caergwrle) or actually traverses a Roman settlement (as at the Ffrith) it has been found to contain Roman coins, fibulae, inscribed altars, brooches, pins, rings of gold, silver and copper, part of an inscribed lamp, etc., or even to cover a hypocaust but this only shows that the Dyke has been constructed since the Romans left the country. There was evidently a Roman settlement at the Ffrith, and when Offa's Dyke was carried through it, the various objects found during the present century were either covered by the Dyke, or thrown up with the earth which was used to make it."

The same writer [A. N. Palmer, Offa's and Wats Dykes. Y Cymmrodor] has pointed out the very great inherent improbability of so extensive and impressive a work having had no name attached to it if it were built before Offa's time. The unanimity of Welsh and English writers, and of Welsh and English place-names, in the neighbourhood of the Dyke, as connecting it with Offa, is also dwelt on.

Turning to the historical evidence, contained in early chronicles, one item standsout pre-eminently in importance. The earliest mention of the Dyke occurs in the Life of Alfred the Great by Asser, who was the King's contemporary and friend. As Asser lived within a century of the date assigned to the building of the Dyke his testimony is of special value. William of Malmesbury tells us that "from St. David's he [Alfred] procured a person named Asser, a man of skill in literature, whom he made bishop of Sherborne." Asser's allusion to the Dyke is as follows: "There was in Mercia in recent times, a certain valiant king, who was feared by all the kings and neighbouring states around. His name was Offa, and it was he who had the great rampart made from sea to sea between Britain and Mercia."

There are several twelfth-century allusions to the Dyke. The first of these is in the Life of St. Oswald1 and is as follows: [translation] "This place [Maserfeld] is distant from the Dyke of King Offa, which divides England and North Wales, scarcely half a mile, from Shrewsbury quite seven miles, and from Wenlock Abbey, towards the south, about sixteen miles. The aforesaid Dyke King Offa formerly constructed, entrenched within the defence of which he abode the more securely from his Welsh enemies. For, in his time, continual strife existed between him and the Welsh so that he could by no means get the upper hand of their assaults or ambushes, except with this protection. From sea to sea, therefore, it hemmed in almost all his land towards Wales, and he fixed that Dyke to be the boundary of the land of either." Simeon of Durham has a brief allusion to the Dyke: " Beorhtric king of the West Saxons, took to himself Eadburgh, a daughter of a king of the Mercians, Offa by name, who ordered to be made between Britain and Mercia the great dyke, that is from sea to sea."

At first sight it seems almost incredible that a king of Mercia should carry through so huge an undertaking as this great Dyke. But when we come to study the records of his reign we realize that we have to deal with a king to whom Charlemagne wrote in terms as of one equal to another. The ruler whom Charles the Great addressed as his " esteemed and dearest brother Offa " must have had vast resources at his back, and have been regarded by that all-powerful king as a force to be taken into account in European politics. Offa's assumption of equality in the negotiations between them regarding their children's marriage is sufficient proof of his power.

In the second half of the eighth century England was split into three kingdoms of nearly equal power. These were Northumbria in the north, Wessex in the south, and Mercia in central England. It is with this Mercian kingdom that we are concerned in its relation to the construction of the Dyke. In 758 Offa ascended the throne of Mercia. In the course of his reign he conquered those portions of the Mercian kingdom which had been wrested from it in the preceding reigns by Wessex. The accounts that have come down to us exhibit his character as a very mixed one. His biographers all speak of his great personal courage, and we hear of his love of reading, and his endowment of a Saxon school at Rome. He drew up a Code of Mercian Laws (" Offa's Code ") which has unfortunately been lost. On the other hand William of Malmesbury calls him "a downright public pilferer," and says he took the lands of many churches. The basest deed attributed to him was the betrayal and murder of a guest under his own roof. Ethelbert, King of the East Angles,-East Anglia being one of the small portions of England outside the three great kingdoms,-wished to obtain the hand of Ethelthryth, Offa's daughter. With this end in view he set out for Mercia, and on reaching the border, sent letters before him announcing his approach. According to this story, Offa replied by a warm invitation, gave his guest a splendid reception, and then caused him to be assassinated while passing through a dark passage.

William of Malmesbury, in his Chronicle, endeavours to sum up the pros and cons regarding Offa's character, and evidently finds the problem a difficult one. After telling us that Offa was " a man of great mind, and one who endeavoured to bring to effect whatever he had preconceived," he continues " when I consider the deeds of this person I am doubtful whether I should commend or censure. At one time, in the same character, vices were so palliated by virtues, and at another virtues came in such quick succession upon vices that it is difficult to determine how to characterize the changing Proteus." During his reign Offa raised Mercia to a position it had never before held.

According to one account Offa followed up the construction of the Dyke by the immediate occupation of the Mercian march. " Offa drove the Welsh beyond the Dee and Wye, and filled with Saxons the plain and more level regions between those rivers and Severn." Thomas Churchyard, an Elizabethan writer, embodies in his Worthiness of Wales a tradition that the space between Offa's and Wat's Dykes was neutral ground.

The power of the famous ruler of Mercia, who was the greatest king of the largest kingdom of the Heptarchy and the ally of Charlemagne, was at least as adequate for such an undertaking as that of any other chieftain who can be easily discovered. His reign lasted for nearly forty years. And if he maintained or employed the dyke, or even a portion of it only, his name, by a proceeding which is a very common one, would be probably given to the whole. The work may have been one of many years, a long continued effort of the Saxons to circumscribe the limits of their British neighbours, and Offa's share in it may have been magnified, as that of Cromwell's has been in the Parliamentary sieges of the Civil War.

The force of the objection, viz., that the dyke is not adapted for defensive purposes, can be estimated by those who have examined it. One may at once concede that Offa's and Wat's Dykes can never have been meant for ramparts to be lined continually with men. In some places they occupy strong positions, in others unquestionably they are very weak. But taken in conjunction with the numerous camps which are found at intervals along their course, and with many of which they were undoubtedly connected, they seem to be well calculated to serve as a frontier barrier against Wales.

Offa's undertaking is not to be discredited simply on the ground that it proved to be insufficient.

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