Offa

Offa (reign 757-?) was the greatest of the kings of Mercia? during its short period of supremacy over England in the eighth century. His power spread over such a large part of England, that he prided himself to be the king of England; he was the only king of Western Europe to be regarded as an equal by Charlemagne. He is famous for setting up Offa's dike, delineating the boundary between England ad Wales. He introduced silver coinage in England. After his death, the kingdom soon got into decline. Only 25 years after his death (825), the role of leading English power had been taken over by Wessex.