The MHRA Style Guide Online
A Handbook for Authors and Editors • Third Edition
From Chapter 3, 'Names'
3.3 Personal Names
Care must be taken over the spelling of names in Mc, Mac, etc. (e.g. McDonald, MacDonald, M’Donald, Macmillan, Mac Liammóir); adopt the form used by the individual in question. All such forms, whatever the spelling adopted, are alphabetized as if they began with Mac.
Likewise, distinguish between Irish names that retain their original form (Ó Máille) and those that are anglicized (O’Donnell).
In Welsh names, ap and ab are neither capitalized nor hyphenated. Names of historical figures are alphabetized under the first name (e.g. Dafydd ap Gwilym, Dafydd ab Owain), modern names under ap or ab (e.g. ap Gwilym, ab Owen Edwards).
Where generally accepted English forms of classical names exist (Horace, Livy, Ptolemy, Virgil), they should be used.
Names of popes and saints should normally be given in their English form (Gregory, Innocent, Paul, St Francis of Assisi, St John of the Cross). In a philosophical context, the title of saint may be omitted (Thomas Aquinas, Augustine of Hippo).
Names of foreign kings and queens should normally be given in their English form where one exists (Charles V, Catherine the Great, Ferdinand and Isabella, Francis I, Henry IV, Victor Emmanuel). Those names for which no English form exists (Haakon, Sancho) or for which the English form is quaint or archaic (Alphonse, Lewis for Alfonso, Louis) should retain their foreign form. If in the course of a work it is necessary to refer to some monarchs whose names have acceptable English forms and some which do not, in the interests of consistency it is better to use the foreign form for all:
the reigns of Fernando III and Alfonso X
Henri IV was succeeded by Louis XIII.
In case of ambiguity as to the correct spelling of names of French authors, use as a guide the catalogue of the Bibliothèque nationale de France (http://www.bnf.fr/). Surnames in van take a lower-case initial in the Netherlands (van der Plas, van Toorn) but are generally capitalized in Belgium (Van den Bremt, Van Ryssel).
With reference to the Prophet, use the form Muhammad and not Mohammed or Mahomet. Likewise, Muslim not Moslem or Mohammedan, Muhammadan, etc.
Various systems exist for the transliteration of Russian and other languages using the Cyrillic alphabet. Contributors to journals, series, etc. in the field of Slavonic studies should ascertain which system is preferred and conform to it strictly. The MHRA specifies that the Library of Congress system without diacritics is to be used in all its publications in the Slavonic field, namely The Slavonic and East European Review, the Slavonic article and review sections of The Modern Language Review, the Slavonic sections of The Year’s Work in Modern Language Studies, and relevant volumes in the Publications of the MHRA, MHRA Texts and Dissertations, and MHRA Bibliographies series. Thus for instance:
Dostoevskii, Chaikovskii, Tolstoi, Evtushenko
In other contexts, Russian and other Slavonic names should, wherever possible, be given in the form recommended by the New Oxford Dictionary for Writers and Editors, even when this conflicts with the Library of Congress system:
Dostoevsky, Tchaikovsky, Tolstoy, Yevtushenko
Note in particular that, except in the one case of Tchaikovsky, Ch- not Tch- should be used (e.g. Chekhov) and that the prime (′) should not be used:
Gogol, Gorky, Ilya (compare Library of Congress: Gogol′, Gor′kii, Il′ia).