I HAVE BEEN working on this book for nearly seven years, and have discussed issues relating to it with nearly every late Romanist and early medievalist I have met during that time; I have gained insights from too many people to list. First of all, I should like to thank those who commented on sections of the book: Leslie Brubaker, who read almost the whole text; Paul Fouracre, John Haldon, Hugh Kennedy, and Eduardo Manzano, who read sections of Chapter 3; Mayke de Jong, Paul Fouracre, John Haldon, Guy Halsall, Peter Heather, Eduardo Manzano, and Peter Sarris, who read sections of Chapter 4; Jean-Pierre Devroey and Domenico Vera, who read sections of Chapter 5; Steven Bassett, Nicholas Brooks, Wendy Davies, Simon Esmonde-Cleary, and Patrick Wormald, who read Chapter 6; Steven Bassett, Matt Innes, and Peter Sarris, who read sections of Chapter 7; Sonia Gutiérrez, Helena Hamerow, Simon Loseby, and Mark Whittow, who read sections of Chapter 8; Domenico Vera and Chris Dyer, who read Chapter 9; Simon Loseby, who read all of, and Lisa Fentress and John Haldon, who read sections of, Chapter 10; Paul Arthur, Lisa Fentress, Jodi Magness, Olga Magoula, Eduardo Manzano, Paul Van Ossel, and Bryan WardPerkins, who read some or all of Chapter 11. They were often sharp critics, and I gained immensely from their insights, suggestions, and bibliographical references; I know they do not all agree with my conclusions.
Another group of people, partially overlapping, consists of friends with whom I started when I needed to get a sense of the bibliography of a given region: people I could not do without as guides to one area or another. These include Steven Bassett, Julio Escalona, Simon Esmonde-Cleary, Lisa Fentress, Riccardo Francovich, Hugh Kennedy, Eduardo Manzano, Ulf Näsman, Pierre Ouzoulias, Claude Raynaud, Peter Sarris, and Paul Van Ossel. I must also here express my great debt to Rosamond McKitterick, Ghislaine Noyé, and Pierre Toubert, who invited me to teach in, respectively, the University of Cambridge (to give the 2003 Trevelyan Lectures), the École des Chartes, and the Collège de France; the lectures I gave there are all, in more or less revised form, in this book and I gained enormously from the conversations and library access—and the time to research and write—that I had both in Cambridge and in Paris.
I benefited from ideas and bibliographical or other help from, apart from those mentioned above, Stuart Airlie, Donald Bailey, François Baratte, Bernard Bavant, Andrea Berlin, François Bougard, Monique Bourin, Alan Bowman, Luis Caballero, Federico Cantini, Gill Clark, Simon Corcoran, Bill Day, Paolo Delogu, Archie Dunn, Santiago Feijoo, Laurent Feller, Rebecca Foote, Sauro Gelichi, Sharon Gerstel, Mary Harlow, Jill Harries, Catherine Hills, Richard Hodges, Sonja Jilek, Jeremy Johns, Olga Karagiorgiou, Sean Kingsley, Luke Lavan, Stéphane Lebecq, Régine Le Jan, Wolf Liebeschuetz, Antonio Malpica, Cyril Mango, Alessandra Molinari, Jinty Nelson, Margaret O'Hea, Lauro Olmo, Helen Patterson, Walter Pohl, Andrew Poulter, Dominic Rathbone, Mark Redknap, Paul Reynolds, Charlotte Roueché, Riccardo Santangeli, Sven Schütte, Chris Scull, Trish Skinner, Jean-Pierre Sodini, Frédéric