I recall reading somewhere that today's dialect spoken in the Baltimore-Philadelphia-Pittsburgh region hasn't changed much since Revolutionary times and is presumed similar to how English sounded in England at that time.
That's interesting, too. Hadn't seen or experienced that. After I posted, I realized it is possible to change one's accent. Which was the nightly news Canadian, think it was Peter Jennings. His speech was just like midwesterners.
Somehow those of us who have ancestors from anywhere do no longer speak like they probably did. Going back to the 1600's in New England, if their writing is any indication, we might not understand their manner of speaking.
It all had to have changed due to inculturation and the melting pot but doesn't explain your exception.
I would disagree. In Philadelphia, for instance, a skilled listener can tell which neighborhood of the City you are from, and your probable ethnicity and religion. Baltimore, the same. DC is harder, because it has so many carpetbaggers and frequent turnover from the political class. And Pittsburgh is west of the influential German-based Amish area, so it has a distinct difference from Philadelphia, which has English/Swedish early influences, followed by Irish, Polish, African-Americans and Italian.
Also interesting to me, who has lived in Philly, Balmer and DC, are discernable differences in African-American speech patterns in those three areas.