IT IS NOW fifty years since I began researching and writing about the history of caliphs from different eras and areas of Muslim history, starting with the Abbasids, the subject of my PhD at Cambridge under the enthusiastic guidance of the great Martin Hinds, a brilliant scholar who died far too young, and moving on to write about Umayyads, both in Syria and the Iberian peninsula, and the Almohads. The half-century which has passed since I began work has seen the subject of caliphate moving from the status of a historical relic to the forefront of modern political debate, and this transformation has encouraged me to explore beyond my comfort zone to examine the way in which ideas the office has been used and exploited through the ages.
Inevitably in such a long sweep of history, I have been ‘standing on the shoulders of giants’ and using the works of scholars more learned and distinguished than myself. I have tried to acknowledge at least some of these debts in the notes and bibliography and I must apologise to any I have inadvertently omitted.
Much of this book was written on the beautiful Greek island of Amorgos, looking out from the terrace of Marco’s house over the olive groves to the white houses of the little port of Aigiali, with the wine-dark sea and the islands beyond.
But however important the calm and peace may be for writing, the book was conceived and formed in the busy cross-current of ideas and debates in the School of Oriental and African Studies in the University of London, where I work. There cannot be an academic environment on the planet where so many ideas and cultures come into daily contact, and ideas of history and community are explored with such vigour. I have benefitted enormously from my interactions with staff and students and perhaps especially by discussions with my numerous Muslim students about the nature and ethics of political power in an Islamic context.
This book has also benefitted from the enthusiasm of colleagues in publishing, my wonderful agent Georgina Capel who is so enthusiastic about my ideas, Laura Stickney at Penguin Books who has supported this project from the beginning and my copy-editor Claire Péligry who has saved me from so many errors and confusions.
And finally from the support of my wife Hilary and my growing family, Katharine, Alice and James and the next generation, Ferdie, Ronja and Aurora, all of whom have supported me (and distracted me in the nicest possible way) in the course of writing.