From 1969 to 1972, he was a
postgraduate student within the Faculty of Oriental Studies, University of Cambridge.[2] He completed his
Doctor of Philosophy (PhD) degree in 1978 with a
doctoral thesis titled Politics and the political élite in the early Abbasid Caliphate.[3]
In 2007, he left the University of St Andrews to join the
School of Oriental and African Studies (SOAS),
University of London.[1] He was appointed Professor of Arabic at SOAS.[2] From January 2015 to January 2018, he is leading a project at SOAS titled Economic integration and social change in the Islamic world system, 800-1000CE; it is being funded by the
Leverhulme Trust.[4]
1996, Muslim Spain and Portugal: a political history of al–Andalus (London,
Longman) (
ISBN0 582 299683)
1998, Egypt as a Province in the Islamic Caliphate, 641–868 // The Cambridge History of Egypt: Vol. 1: Islamic Egypt / edited by Carl F. Petry (Cambridge,
Cambridge University Press)
ISBN978 0 521 47137 4
2001, The Armies of the Caliphs: military and society in the early Islamic State (London,
Routledge) (
ISBN0 415 25092 7)
2001, The Historiography of Islamic Egypt, c. 950—1800, editor (Leiden and Boston:
Brill) (
ISBN978-9-004-11794-5)
2013, Crisis and Continuity at the Abbasid Court, with Maaike van Berkel, Nadia Maria El Cheikh and Letizia Osti (Leiden,
Brill Publishers)
ISBN978 90 04 25271 4
2020, The Rise and Fall of the Early ʿAbbāsid Political and Military Elite // Transregional and Regional Elites – Connecting the Early Islamic Empire (Studies in the History and Culture of the Middle East, vol. 36) / edited by Hannah-Lena Hagemann,
Stefan Heidemann (Berlin,
Walter de Gruyter GmbH & Co KG)
ISBN978 3 110 66656 4