The History of Britain Revealed - the Eretide of Britain Uncovered - is a book that withersays the mainstream belief of the ordfrume of English. It says that English does not stem from Anglo-Saxon but was already spoken in Britain. The incomers would not have been manyful enough to have taken over most of the land. Eventhough there are many French words in Middle and New English, Old English is swith unlike from Middle English and so could not have become the latter. The English tung is unalike from A-S or Old Norse and so is bethought as a standoff tung, eventhough sharing some marks with other rerdes like Frish and lesserly to Danish, Thedelandish and other akin tungs. English, for byspell does not have raised sounds and is the only rerde of its kindred of which r is said as we know of..
For a deeper insight:
http://moderntribalist.blogspot.com/2007/03/was-english-spoken-in-england-before.html