Great subject, although claims that the U.S. accent is closer to Shakespearean, I think is a stretch.
When I think about U.S. accents, starting at the East coast and moving West, there are clear regional differences.
There are distinct Boston, New York, and Phillie accents, and yet the people outside of these big cities have a different accent. Pittsburgh even has
its own unique accent, and arguably Chicago.
The Southern accent seems much more homogeneous to me. From Virginia to Georgia, to the Mississippi River, including Arkansas and Oklahoma, the
accents sounds fairly similar.
Then there is the hillbilly accent, as I would call it. This would be Kentucky, Northern Tennessee, Southern Indiana, Southern Illinois, and maybe
even Southern Ohio. This particular version of English would use phrases like Y'all reckon, and Warsh yourself. These areas are originally the
first wave from the Northern Colonies following the trail blazed by Daniel Boone, and I had an ancestor who helped explore and survey the Ohio River
Valley who came from New York, outside of the city. I would also add, that where I grew up, there were many people who had some native American
heritage. Living in California where there are many mixed European Asian children, I can clearly see that many of the people who can't trace their
ancestry back to immigrants from a few generations have this mixed look.
New York was originally settled by the Dutch, and after the Revolutionary War, a great many Germans migrated to the U.S.. I thought that the Irish
immigration, along with the Italian, came much later. Of course, there has always been a steady stream of Eastern Europeans as well, and the French
had a considerable presence in Canada, New Orleans, and a smattering throughout the Louisiana Purchase territories.
It also seems to me that there is a particular Western Accent that is developing from the rocky mountain states, a California surfer based accent, and
a North West Coast accent.
It seems that accents drift fairly quickly.
I would think that there would be a lot more influence to change the U.S. accent than the British accent, or the English accent.
Wasn't there a feud that developed between Britain and Europe over whether or not Newton or Leibniz developed calculus, and a period of time where
Britain and Europe were somewhat isolated from each other?
I also have to wonder how much India influences the development of the modern day British accent.
There is a standard American accent taught in schools, popularly used by broadcasters, and in most movies, that I believe is Northern Midwest
Here is a site in linguistic, and what it has to say.
The two most commonly taught accents (in the world as a whole) are both rather artificial: 'General American' (more or less a Mid-Western and
West Coast accent, and used by some high prestige speakers outside this region too); and the British accent 'RP' (which developed in the private
boarding schools of the nineteenth century, and is associated with high prestige groups in England). Both these accents are used over a wide
geographical area, though in world terms both are regional accents (General American is a US accent, and RP is an accent of England). They are heard
more, by more people in the country, than are accents which are associated with a smaller area: so people are familiar with them. These accents are
the ones transcribed in dictionaries. Because they are used over wide areas, and used by people of high social class, they are seen as being suitable
to teach to foreign learners of English. For this reason, they are called 'reference varieties'.
Now here is a funny one to think about.
One island of early Scotch-Irish English speech was left behind and preserved during the push west. This special, archaic variety of English is
known as Appalachian English. It preserves many archaic features that date back to earlier stages in the development of English in Britain. Forms
thought to be substandard today are actually the outmoded standard of yesterday. A good example is the use of double negatives such as 'not
nobody.' Linguists have dubbed this variety of English as "American Old English" or "American Anglo Saxon". Other mountainous, relatively
isolated areas of the American East show a similar preservation of archaic speech. Mario Pei, a popular writer on linguistics, said that "The speech
of the Ozarks comes closer to Elizabethan English in many ways than the speech of modern London."
--Retention of preposition in the progressive aspect: I'm a talking to you.
--propensity to use compound nouns: men-folk, man-child, kin folks
--fixin to, pert near, afeared, beholden (indebted), took sick, upped an, mess of (lot of)
--Rhyming euphemisms: swan, swanny = swear, land sakes alive, golly, dad blamed.
--Special distance words: This here, that there, that yonder.
So Shakespeare actually spoke more like a hillbilly from the Missouri area, Ah reckon.