The Anglo-Saxons lived and ruled in Britain between 1,500 and 1,000 years ago.
Offa was an important king of Mercia, the English Midlands.
Offa is best known as being responsible for Offa's Dyke, as important, although not as famous, as Hadrian's Wall that separates England from Scotland.
In the late late 9th-century a writer called Asser 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".
Offa's Dyke may have been started well before Offa's time, perhaps in the earliest years of Saxon control, around the 500s AD, when Saxons arrived in Britain and invaded and settled farther and farther west. It may have been the place where the Welsh kings finally drew a line against Saxons expansion. If so, as a line is is nearly 1500 years old.
This ditch and bank as we see it today are certainly over 1300 years old, and although it is simply dug earth, it has survived despite the weather, and in some places, ploughing by farmers.
The ditch is on the western side, which is why people thing the English were protecting themselves from attacks by the Welsh.
It still runs relentlessly from the coast at the Bristol Channel to the North Sea opposite Liverpool, some 240 kilometres, or 150 miles. The dyke is only missing where hills and steep slopes did the same job of defence. And all of it was dug using only picks and shovels.
It is named after Offa, the Anglo-Saxon king of Mercia from AD 757 until 796, because it was probably he who caused the older bank to be strengthened, and made taller, and who also may have had a long line of wooden stakes – a palisade– put on the top.
When it was finished, Offa's dyke – both the bank and the ditch that supplied the soil for the bank – was up to 20 metres, some 65 feet, wide and two and a half metres, some 8 feet, high
So how did it get built? In those days, lords owed services to their king, and so each section may well have been built by servants of the lords to fulfil the demand of the king.
Many legends, unsupported by facts, are connected to the dyke. For example one legend claims that it was customary for the English to cut off the ears of every Welshman who was found to the east of the dyke, and for the Welsh to hang every Englishman whom they found to the west of it.
