Procopius was the major historian of the reign of Justinian and one of the most important historians of Late Antiquity. This is the first extensive commentary on his Persian Wars since the nineteenth century. The work is among the most varied of the author, incorporating the history and geography not only of Mesopotamia and the Caucasus, but also of southern Arabia and Ethiopia, Iran and Central Asia, and Constantinople itself. Each major section is introduced by a section on the history of the events concerned and on the treatment of these events by Procopius and other sources. The volume is equipped with an introduction, three appendices, and numerous maps and plans. All sections of the work that are commented on are translated. The book will therefore be of use to specialists and the general reader alike. A complete translation of the work, with lighter annotation, is being published separately.