This study began life as postgraduate research at the University of Birmingham, under the supervision of Chris Wickham. I am greatly indebted to him for his guidance, and continue to benefit from his advice. Graham Loud has been generous in his support, and his help and suggestions are much appreciated. It has been my good fortune to meet David Abulafia, whose encouragement led me to pursue the Gaetans further afield. I am indebted to Lucia Travaini, who has provided me with invaluable insights into the problems of southern Italian coinage.

I have been aided in revision work and further research financially by the British Academy and the British School at Rome. I owe a debt of thanks to the librarian at the latter, Valerie Scott; to don Faustino Avagliano, at the Archive of Montecassino, for his good-humoured assistance; and to the library staff at the University of Birmingham, whose persistance has unearthed many gems which I would not have expected to find in England. I also received much valuable assistance from the staff at the Archivio di Stato in Naples, especially from Elvira Pollastro; many of the placenames would not have come to light without the help of the staff at the Ufficio Catastale in Latina, particularly Messrs. Alfonzo Fiorito and Mario Gucciardo.

Rosamond McKitterick's editorial comments have been acute and stimulating, and I am grateful for her help in developing the final version of the study.