This book has been long in gestation, and in that time I have incurred innumerable debts. My thanks are due in the first instance to the British Academy, whose three-year studentship provided the necessary financial support for my doctoral research completed in Cambridge in 1996, and upon which much of this book is based. A smaller British Academy grant facilitated a subsequent follow-up visit to the Rhenish archives in 1998. Financial support for research in Germany in 1994/5 was provided by the European Commission-administered ERASMUS Inter-University Co-operation Programme, for which I offer my thanks. I must also record my gratitude to Nuffield College, Oxford, for the Prize Research Fellowship they awarded me from 1996 to 1999. This, together with grants from the College, allowed me to conduct additional archival research in Berlin in 1997, and to attend conferences around the world where I benefited from those exchanges that are so essential to academic scholarship. This book has evolved and matured through such exchange and discussion. With this in mind, my greatest debt of all is to Professor Tim Blanning, my doctoral supervisor, whose criticism and encouragement, not to mention practical assistance, has proved invaluable over the last nine years. I am also deeply grateful to Professor Wolfgang Schieder, for the welcome he extended me during my visits to Cologne, and to Dr Geoffrey Ellis and Dr Brendan Simms.