I recently wondered why, in American movies and TV shows set in foreign or imagined lands, the characters almost invariably speak in British accents, and whether there’s a literary equivalent. I can now report some news on the topic.
First, there has been a lot of discussion about the general phenomenon. One commentator theorized that, on the fantasy end of things (on up through Game of Thrones, where poor Peter Dinklage is made to talk British), it’s the responsibility of J.R.R. Tolkien, author of the books that started the genre, The Hobbit and The Lord of the Rings: “even though Middle Earth is a fantasy world it’s clearly inspired by England. Thus it’s not unreasonable that the characters sound like they come from the country that has such a heavy influence on the settings in Middle Earth.”
The invaluable website TV Tropes came up with a name for the custom–“the Queen’s Latin”–and has this explanation for its use in historical dramas:
Britain’s long history causes British accents to seem somehow “older” — they are used to suggest a sense of antiquity. This is actually inaccurate from a linguistic perspective; the modern British accents actually represent a more evolved form of English. Older English accents were closer to modern Irish and American accents.
In any case, using the Queen’s Latin makes a series or film commercially viable in the U.S. It alleviates the need for subtitles, while maintaining the appearance of historical authenticity. It’s just foreign and exotic enough. (Many British actors already Play Great Ethnics.) It’s also no doubt inspired by productions of Shakespeare‘s plays set in Ancient Rome. Remember: Romeo might have been Italian, but he’s not realistic unless he talks like a proper British toff.
The other new thing is another example of literary Queen’s Latin, from the novel All the Light We Cannot See. The book is set in France and Germany during World War II, yet the author, Anthony Doerr — an American— frequently uses British terms: crisps instead of potato chips, lift instead of elevator, and biscuits. (The last is a reversal of the English rapper Lady Sovereign’s couplet “Some English MCs get it twisted/Start sayin’ ‘cookies’ instead of ‘biscuits.’”)
The lingo doesn’t make sense, but I suppose it adds to the feel of the book as taking place in a long-ago era.
notoneoffbritishisms.com 
In the ‘old days’ in Hollywood films the ‘bad’ cowboys used to wear black hats and the ‘good’ cowboys white ones. Now the baddies tend to have British accents – leaving me surprised that when visiting the US most Americans react positively to my accent (particularly the women).
However, in the Deep South almost everyone I spoke to thought I was from Boston – and the reaction was not always positive
I remember people complaining about the fact that Scorsese cast a mix of British and American accents in “The Last Temptation of Christ”. Some people were really put off by Harvey Keitel’s New York accent in his role.
Switching the focus slightly, after years of watching British dramas, mysteries and Britcoms on PBS, it occurred to me while watching an episode of the reincarnated “Poldark” a couple weeks ago that one reason I like the BBC’s period dramas more than some others is that they are much more meticulous about using proper grammar in the dialogue.
I think it’s not so much “British accents” as it is southern English middle or upper middle class accents. There’s a great range of British accents, few of which would be heard in an American movie.
The thing to note about the range of British accents chosen is that (almost?) never include identifiable urban accents – you won’t hear Liverpool or Birmingham or Glasgow in “Game of Thrones”, just broadly regional ones, which even to British ears sound relatively timeless, or at least pre-industrial. The only exception seems to be London, whose accent is clearly thought to be a reliable marker of the less than honest section of the working class.
The standard/BBC english is different enough for the American ear to sound foreign and still be understandable.
This is exactly what I was going to say. Americans can only with difficulty understand an authentic regional British accent spoken rapidly, but we’re used to what the next commenter calls RP. It connotes an exotic origin without making us strain to understand the words.
Rather than southern English as such, the accent being discussed here is Received Pronunciation/RP, which was also traditionally used among high-social status groups and drama throughout the British Isles & Commonwealth (a few elderly Australians still use it in everyday speech, although it’s dying quite rapidly).
Listening to old US talkies and radio plays, actors and announcers on those also tend to adopt a slightly Americanised version of RP, presumably for gravitas. I’d be surprised were the same not true for early 20th-century US stage productions (where the characters weren’t identifiable US working-class).
Presumably, this recombined with the widespread availability of British character actors in Hollywood (and later, cheaper filming costs in European locations) to produce the current situation.
Can I just say that the whole ‘American accents are closer to older English accents’ is a complete load of bollocks. The only similarities are that American accents are rhotic, as were older English accents, that’s it though. https://m.youtube.com/watch?v=gPlpphT7n9s
Watch that, it sounds like a westcountry accent which is still alive today. Sounds nothing like any American accent either.
Just seems to be one of those silly things people parrot without knowing what they’re talking about.
There is a very interesting range of accents in “Game of Thrones”. Most notably, the Stark family – analogous to the Yorks in the War of the Roses – are from the North, and the male family members either have (e.g. Sean Bean from Sheffield, playing Ned Stark) or adopt (e.g. Kit Harington from London, playing Jon Snow) broadly Yorkshire accents.
However, the family’s two daughters (Sansa Stark played by Sophie Turner from Northampton, and Arya Stark played by Maisie Williams from Bristol) do not adopt Northern accents, and instead – as far as I can tell – use their own voices to play their characters.
Their principal antagonists (at least early in the series) are the Lannisters (Lancasters), who far from speaking like Mancunians as one might expect, speak RP – or, in the case of Jamie Lannister (played by Nikolaj Coster-Waldau) English with a distinct Danish accent.
In the wider world of the story, there are also stray Newcastle, Irish, and Norwegian accents floating around – and that’s only counting those characters who speak in the Common Tongue, the show’s equivalent of English.
Re. the above comment. I believe that the actresses who play the Stark daughters might as well be from anywhere in England as they barely have regional accents at all. If Maisie Williams is from Bristol then her presumably middle class upbringing (or stage school) has eradicated any West Country burr.