The most Archaic accents are those from the rural southern US. (other than the real Dublin Accent that is, ) Many of the word pronunciations , word use, and phraseology my be Elizabethan. So the back woods frontier accents are the oldest. The Dublin Accent is thought to be the oldest form still spoken, but it may have more word meanings and phrases at its root than the pronunciation.
The Generic American Accent goes back to the brake with England and you can see the similarities with Canadian English. Also Americans had fixed their spelling of words prior to the Revelation.
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