Why are fantasy world accents British?

[Bêthberry]

Originally Posted by Kuruharan

Tempting as that theory is, I think it would be easy to overstate the influence of the Bard in that way.

I think it has a lot more to do with the fact that in the English speaking world the cultural antecedents during the middle ages were largely in England.

Possibly, although there are large pockets of the English speaking world that also include other medieval cultures, such as the strong influence of French in Canada.
But there are in fact a great many summer theatres over here that are devoted to Shakespeare, not exclusively maybe, but with a primary focus. We even have a Shakespeare in the Park summer group. Certainly he is taught in schools whereas Chaucer and, for instance, John Milton are not.

There is another hugely influential form of Renaissance English that might still be well known here and which connotes "old English" or "old tymes" and that is the King Jame Bible. There are many English speaking Protestants here (well, at least in Canada) who still consider the KJB to be the superior translation to the myriad modern ones.

And for anyone into New Age stuff, one of the influential books is A Course in Miracles, in which a psychology professor alleges to channel a new message from Jesus. And it's entirely in a mishmash of KJB English. That might not be a hugely popular cultural influence but I think it suggests how strong is the nostalgic sentiment for old forms of the language as representative of something "not modern", not secular, not of the rational materialist perspective.

Just a suggestion (as I'm not a New Ager).