The Roman Empire has been the object of serious research for around a century and a half and imperialism has never been off the agenda. It would be impossible to provide a complete guide to the scholarship on which this book is based, and I have not tried to do so. Each chapter is followed, however, by a few suggestions for further reading. I have recommended only work available in English and have tried to pick the most exciting and most recent works, since new research continues at an astonishing pace. I have also added a few notes to each chapter, some identifying the source of particular quotations or key passages of ancient writers, some acknowledging the source of particular ideas or acknowledging books or articles that were especially helpful when I was writing the chapter. Here too I have concentrated on the most recent work, but I have included a few really crucial items written in other languages. After all, the study of antiquity is an international venture, and the Roman Empire is bigger than any of us.
The bibliography at the end of the volume gathers together all works cited, but cannot claim to be a comprehensive guide to the subject. Fortunately in the twenty-first century we benefit from a number of very recent and authoritative reference works on all aspects of Roman history. The best one-volume reference work to all aspects of antiquity is the Oxford Classical Dictionary (4th edn. 2011). The revised Cambridge Ancient History devotes seven volumes to Rome (1989–2005). The first volume of the New Cambridge Mediaeval History (2005) is also relevant to the end of this story, as is the Cambridge History of the Byzantine Empire (2008), the Cambridge Economic History of the Greco-Roman World (2007), and the first volume of the Cambridge History of World Slavery (2011). Harvard’s Late Antiquity: A Guide to the PostClassical World (1999) combines thematic essays with a dictionary. The best multi-volume dictionary is Brill’s New Pauly (2007). All these works are available on-line, as well as in hard copy. The Barrington Atlas of the Greek and Roman World (2000) is the best guide to the topography of antiquity.