Why build a dyke, and how?

As has already been mentioned, there had been numerous incursions into England by the Welsh. Herefordshire had been devastated more than once, and the city itself taken by the invaders. At the start of Offa's reign the Welsh even managed to reclaim some of the border land, which meant that settlement and agriculture in these areas by the English was very difficult and created an unstable frontier. The decision was therefore made to construct a boundary that would enable the English to defend their territory more easily and prevent further raids. The decision to go ahead with the dyke was a huge one with the question of whether it could be achieved being highly debatable. The manpower needed was enormous but obviously it was thought that the need for a defensive structure was greater.

The fact that the dyke was obviously built as a barrier to the Welsh is evident in its construction. The ditch is always on the Welsh side, and the steepest face of the bank is always on the west.

Before building the dyke, King Offa and his men would have had to plan the route carefully so that particular settlements were included on the English side, and also so that the line followed the less tricky topography and always tried to keep a good view to the west. It is thought that the route may have been laid out using beacons from hill to hill along the route, and that these would have then been used as sighters. The more detailed line would have been laid out with stakes between the beacons. Any undergrowth or woodland would have had to be cleared on the line of the dyke and either side of it so that there was no cover for Welsh raiders. In all probability a plough was then taken along the line to mark the site for digging. The turf that was stripped on the line of the dyke was used to build or front the dyke, and the large bank was made from earth taken to create the western ditch.

The dyke was most probably built using some slave labour and by the enlisting of men from the various villages in Mercia. It is likely that each village was expected to send a certain number of men depending on its size; these men would be from the lower orders of society, those who were used to working on the land. These men would have been accustomed to working long hours with hard work, and the chances are that once you had completed digging your section you would have been allowed to go home, so there was more incentive to work harder! Those men who were not called up for manual work, i.e. the nobility, would probably have been expected to provide food and shelter for the labourers, as well as some of their tools.

[Original author: Miranda Greene, 2005]