- Emeritus Fellow, All Souls College (from 1987 to 2017)
- Honorary Fellow, Wolfson College, Oxford and of Peterhouse, Cambridge
- Senior Research Fellow, All Souls College (from 1962 to 1987)
- Fellow and Tutor of Peterhouse and Lecturer, University of Cambridge (from 1947 to 1962)
- Cabinet Offices (from 1942 to 1946)
- La Storia Manipolata (Rome: Laterza, 1998).
- Modern Italy: A Political History (New Haven; London: Yale University Press, 1997).
- Mazzini (New Haven; London: Yale University Press, 1993).
- Italy and its Monarchy (New Haven; London: Yale University Press, 1989).
- (joint) A History of Sicily (London: Chatto & Windus, 1986).
- Cavour (New York: Knopf, 1985).
- Honorary Citizen, Santa Margherita Ligure (1999)
- Association for Study of Modern Italy (from 1987)
- Honorary Fellow, Peterhouse (from 1986)
- Public Orator, Repubblica di San Marino (1982)
- Foreign Honorary Member, American Academy of Arts and Sciences (1972)
- Sileno d’Oro (1996).
- Fregene (1990).
- Polifemo d’Argento (1988).
- Presidential Medal, Italy (1984).
