how did he get the latter title?
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who is offa of mercia? King of Mercia, a kingdom of Anglo-Saxon England were there any coins bearing the image of the king? No. Coins carried his name. what is his stature? "rex Merciorium", "king of the Mercians and surrounding nations" and Rex Anglorum"
wiki:11603102
Offa of Mercia [SEP] Stature
The title Offa used on most of his charters was "rex Merciorium", or "king of the Mercians", though this was occasionally extended to "king of the Mercians and surrounding nations". Some of his charters use the title "Rex Anglorum," or "King of the English," and this has been seen as a sweeping statement of his power. There is debate on this point, however, as several of the charters in which Offa is named "Rex Anglorum" are of doubtful authenticity. They may represent later forgeries of the 10th century, when this title was standard for kings of England. The best evidence for Offa's use of this title comes from coins, not charters: there are some pennies with "Of ℞ A" inscribed, but it is not regarded as definite that this stood for "Offa Rex Anglorum." In "Anglo-Saxon England", Stenton argued that Offa was perhaps the greatest king of the English kingdoms, commenting that "no other Anglo-Saxon king ever regarded the world at large with so ...