Absolutely true: just as Canadians speak and pronounce a type of French which is closer to what was spoken in the 18th-century, so do (or did) much of the original English-Irish-Scottish populations of the Appalachians - many of whose descendants later fanned out through the South - speak a variety of English often laced with Elizabethan-up-to-eighteenth-and-nineteenth-century words, expressions and pronunciation.
This shows up most beautifully in the so-called 'traditional' songs from the Appalachians that were collected, recorded and preserved by various scholars, including musicologists from the Library of Congress.
I don't have the time - at the moment - to offer some examples, but I'll come back to this post later and do so: not to win a point, but just to offer some lovely music in a wide range of styles - from scholarly to commercial - to those who appreciate it.
http://www.youtube.com/watch?v=DQg4k0GCHpk
And: