Taking 'accent' to mean, as it usually does in non-technical language: 'more or less consistent alterations of the vowels/consonants of "received" English': I should say that, in the cases you query, no accent-differentiation is needed or desirable. For instance, it would probably be better to avoid certain, actual or conventional, features of modern 'vulgar' English in representing
Orcs, such as the dropping of aitches (these are, I think, not dropped in the text, and that is deliberate). But, of course, for most people, 'accent' as defined above is confused with impressions of different intonation, articulation, and tempo. You will, I suppose, have to use such means to make Orcs sound nasty! I have no doubt that, if this 'history' were real, all users of the C[ommon] Speech would reveal themselves by their accent, differing in place, people, and rank, but that cannot be represented when C. S. is turned into English – and is not (I think) necessary. I paid great attention to such linguistic differentiation as was possible: in diction, idiom, and so on ; and I doubt if much more can be imported, except in so far as the individual actor represents his feeling for the character in tone and style. As
Minas Tirith is at the source of C. Speech it is to C.S. as London is to modern English, and the standard of comparison! None of its inhabitants should have an 'accent' in terms of vowels &c. The
Rohirrim no doubt (as our ancient English ancestors in a similar state of culture and society) spoke, at least their own tongue, with a slower tempo and more sonorous articulation, than modern 'urbans'. But I think it is safe to represent them when using C. S., as they practically always do (for obvious reasons) as speaking the best M[inas] T[irith]. Possibly a little too good, as it would be a learned language, somewhat slower and more careful than a native's. But that is a nicety safely neglected, and not always true:
Théoden was born in
Gondor and C.S. was the domestic language of
the Golden Hall in his father's day (Return of the King p. 350).
