Yeah, there's the Tangier Island in Virginia where people have an accent that some claim is closer to the English accent spoken in pre-colonial times: https://news.ycombinator.com/item?id=16320595
I've been to Tangier and the accent there is truly strange. It has a very archaic sound, for sure. And it's not just the accent, there are grammatical differences as well. One branch of my family is from the Great Smoky Mountains region of Appalachia. The accents and speech there also have archaic features due to isolation and influences from Scottish, Irish, and Welsh settlers.
Some years ago, I read Ben's father David Crystal's book "Pronouncing Shakespeare" and it has a whole chapter on how they reconstructed the original pronunciation. In Shakespeare's time, they did, in fact, write about elocution quite a bit, and some clues come from there. And, as others have noted, you see rhymes and puns show up when you revert to the old pronunciations. As I recall, Crystal claimed that he thinks they got it at least 80% right.
