Some readers may notice the lack of consistency in the transliteration of names. I have used proper names that are familiar in anglicized forms, for instance, for emperors Constantine, Justinian, Leo and Maurice, popes Sylvester, John and Gregory, and figures such as Arius and Boethius. Where there is no generally accepted English form of the proper name, I have distinguished rulers of Constantinople and their officials by using the Greek form, ending in -os, from those active in the West, identified by the Latin ending in -us. This means that Anastasios, the emperor, is spelled differently from Anastasius, the pope.
Similarly, for unfamiliar place names I have used the spellings employed in the sources, on both the maps and in the text, adding the modern names where necessary. Both are signalled in the Index, so you can find the contemporary name referred to in the book.
For official titles, I have cited the terms used at the time and added a definition if necessary. Again, both Greek and Latin terms have been transliterated, for example, strategos and apocrisiarius. Naturally, over a four-hundred-year period there are some anomalies.