Still the best succinct and scholarly short history of the crusades is H. E. Mayer, The Crusades (2nd edn, Oxford University Press, 1988). For a more expansive treatment, see C. Tyerman, God’s War: A New History of the Crusades (Allen Lane, 2006). The most seductive if often untrustworthy modern narrative of the First Crusade remains S. Runciman, A History of the Crusades, vol. 1, The First Crusade (Cambridge University Press, 1951, and many reprints since); also, now, T. Asbridge, The First Crusade (Free Press, 2004). For attempts to define what contemporaries tended to assume or avoid, see J. Riley-Smith, What Were the Crusades? (4th edn, Palgrave Macmillan, 2009); C. Tyerman, The Invention of the Crusades (Macmillan, 1998); and N. Housley, Contesting the Crusades (Blackwell, 2006). The cultural milieu was exhaustively and magisterially exposed and explored by C. Erdmann in his classic The Origin of the Idea of Crusade (1935; trans. edn, Princeton University Press, 1977), although he has not lacked critics, who prefer to see the phenomenon of 1095 as less predictable, more exceptional, less political or more pious. Nonetheless, modern study of crusade origins begins with Erdmann. R. Chazan, European Jewry and the First Crusade (University of California Press, 1987), examines the dark aspect of the Jewish pogrom of 1096 and, by implication, much else. Discussion of the acceptability of war by the religion of the Beatitudes prompts F. H. Russell, The Just War in the Middle Ages (Cambridge University Press, 1975), and, more narrowly, M. Bull, Knightly Piety and the Lay Response to the First Crusade (Clarendon Press, 1993), and W. J. Purkis, Crusading Spirituality in the Holy Land and Iberia c.1095–c.1187 (The Boydell Press, 2008). What drove men to join up and what they experienced on campaign concerns N. Housley, Fighting for the Cross (Yale University Press, 2008), and J. Riley-Smith, The First Crusade and the Idea of Crusading (Athlone, 1986), which also considers the role contemporary interpreters played in transmitting a coherent inspirational understanding of the events. How the crusade was presented at the time and later is discussed by C. Tyerman, The Debate on the Crusades (Manchester University Press, 2011). The First Crusade as warfare has encouraged the wonderful study by J. France, Victory in the East (Cambridge University Press, 1994). For a recent attempt at a sociological analysis, see C. Kostick, The Social Structure of the First Crusade (Brill, 2008). Most biographies of the western leaders in English now creak with age. For the crusade’s place in ecclesiastical politics, consult C. Morris, The Papal Monarchy (Clarendon Press, 1989). Islamic attitudes have become increasingly clear to non-Arabists through, for example, P. Holt, The Age of the Crusades (Longman, 1986), and, especially, C. Hillenbrand, The Crusades: Islamic Perspectives (Edinburgh University Press, 1999). A. Maalouf, The Crusade Through Arab Eyes (Al Saqi Books, 1984), says much about modern Arab opinions but little else. Many important aspects of the First Crusade are discussed in The First Crusade: Origins and Impact (Manchester University Press, 1997), ed. J. Phillips. Alexius I awaits a modern English-language biography; meanwhile, for the Byzantine background, see M. Angold, The Byzantine Empire (Longman, 1984), and J. Harris, Byzantium and the Crusades (Hambledon, 2003). For a different, but no more nor less plausible contemporary narrative of the First Crusade, see S. Edgington’s translation of Albert of Aachen, Historia Ierosolimitana (Oxford University Press, 2007).