That the book was written in English by an Englishman shouldn't matter, but many fans insist it does. Tolkien wasn't writing about England, he was writing about Hobbits and the people they came into contact with. In his creation these peoples did not speak English nor anything like it and they did not speak with English accents. In his book they spoke with English idioms because, frankly, to insert false idioms would have made the task immensely more difficult and tedious (although you can detect them here and there, such as "There's no accounting for east and west" in Bree).

: The problem with accents is that arbitrarily assigning a
: particular accent to a particular "race" doesn't make it any
: better. It makes a bit odd and difficult to follow. If you
: keep the accents British (and believe me, there are ways to
: differentiate different kinds of "British" accents), at least
: you're keeping true to the language the book was written in.
: Again, you talk about Westron, Orkish, etc. But that doesn't
: mean anything in the real world. There is only so far the
: fantasy can be carried out, unfortunately.

Some people feel the movie is an attempt at a "realistic" representation of the book. Hence, differentiated accents would indeed be appropriate (Tolkien himself conceded the characters wuold have spoken with differentiated accents, but since that sort of thing was near to impossible to convey in the book, he relied on idiom). The problem with relying upon idiom in the movie to convey a difference in tribe or nation is that the audience won't be able to sit there and analyze the dialogue. We'll have to depend on visual an aural cues, such as mode of dress and accent.

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