>> Ekwall interprets Bredon as a combination of Old British (Celtic if you prefer) Bre meaning a >> hill as in modern Welsh "bre" from the ancient British word "briga" plus the Old English "dun".
But why was a hill called 'Bre'? Was it because hills were sacred to the goddess of that name?
Accepted etymology only works as far back as written language. Words had roots long before they can be traced back in writing. This makes playing with them so much fun :-)
