There are modern ethnic differences which seem different but unless huge pockets of them, not regional.
What has always intrigued me is how all British immigrants started out with the way Britons spoke at the time but don't any more. There are Scottish and Irish brogue's, too; I'm no expert. The Britons still speak with a distinct accent but their descendants to the US unless immigrating very recently like our beloved Piers Morgan, have assumed the older local dialects. Midwestern used to be the one most sought after for TV broadcasting but now it's a tossup with the elitist British accent.
But why do Australians speak with a British accent? Their immigration was a little later but not that much, and several generations have elapsed. Is it because of their relative isolation despite modern communications? Canadians with the exception of the French Quebecois speak like Minnesotans.
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.
I don’t think regional accents are as pronounced as they used to be, I mean southern drawl for example or I haven’t heard many lately y’all.
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Dang! Have you been to Texas?
;-)
Piers Morgan speaks with what is called by most Brits the “posh” accent. It is not a local dialect like what is spoken in Cornwall or other parts of England. (And I was disappointed when visiting Cornwall last year to hear the Cornish accent rarely spoken by most of the locals I met there.) The “posh” accent, like how Tony Blair or BBC announcers speak, is not that common in Britain.
I don't know how Morgan talks, but Martin Bashir doesn't sound very American. Indeed, he may sound more British now than he did in England.
But why do Australians speak with a British accent? Their immigration was a little later but not that much, and several generations have elapsed.
They may sound the same to you (and to most Americans), but Britons and Australians recognize that their accents are different. I suspect that we hear the similarities between the two accents but not the differences.
American regional accents are supposed to have similarities to British regional accents of the 17th and 18th century. Over time they've grown apart. Since British and Australian English started to diverge at a later period, it's likely that the similarities would be greater.
Don't ever tell Australians and New Zealanders that they sound alike, though.
I haven't heard or read "English accent" in I don't know how long. English identity has been completely subsumed into Britishness in a way the others have not.
My apologies if I have misunderstood you.
Aussies and Brits have distinctly different accents, but to many American ears, they sound very similar. Same with the Kiwis.