Giles Constable is one of those historians – Steven Runciman and James Brundage are other examples – who have made major contributions to the history of the crusades in spite of being known best for their research in other fields. Crusading impinged on so many aspects of life in the central Middle Ages that is hard for historians to avoid it. Scholars working, as Constable does, on monastic history are bound to come across valuable material, but not all of them are as perceptive or as rigorous as he has been in recording it. The collection published here comprises thirteen papers and two appendices, which are short papers themselves. Each ends with an explanatory note. Two of the papers and the two appendices are published for the first time. Eight are revised reprints of articles previously published. One combines two articles that were originally published separately. One earlier publication has been divided in two. The concentration is on the twelfth century, but the paper on historiography encompasses much more than that, of course, and the article on the Fourth Crusade considers the years immediately after 1200 in some detail.

Two of the articles changed the course of crusade historiography. Although Constable does not like his work being pigeon-holed, ‘The Second Crusade as seen by contemporaries’, which was published in 1952, was a starting point for the development of an approach, known today as ‘Pluralism’, that defined a crusade, in Constable's own words, by the way it ‘was initiated and organized’, rather than by its goal. The participants in the lively debate it helped to generate have now retired, exhausted. On the other hand, the ripple effect of ‘Medieval charters as a source for the history for the crusades’, a landmark paper delivered at the first conference of the Society for the Study of the Crusades and the Latin East and published in 1985, can still be felt. It opened the eyes of historians to sources in monastic cartularies that they had ignored. More and more new material is now coming to light, relating precisely to those centuries which historians used to believe were over-worked.

Other papers reinforced trends in historical thought that were already in evidence. ‘The financing of the crusades’, published in 1982, was a very significant contribution to a continuing discussion on the costs of crusading to individuals. ‘The place of the crusader in medieval society’ and ‘The military orders’, originally one article published in 1998, reflected the growing interest in the ideology of crusading and its attraction in religious terms, as does ‘The cross of the crusaders’, which is the first comprehensive survey of material relating to the crosses of crusaders and pilgrims in the twelfth century, and ‘The Fourth Crusade’, in which Constable stresses the religious motivation of the participants.

Of the other articles in the collection, ‘The historiography of the crusades’, first published in 2001 and here expanded to take in the development of crusade studies in America – treated by Constable in more detail than it was in a paper written some years ago by Hans Mayer – is supplemented by the appendix on ‘The numbering of the crusades’. It was for several years the last word on the subject, but changes in the field are so rapid that at present nothing seems to be the last word for very long and in some ways it has been superseded by Norman Housley's Contesting the crusades, although Constable's interests are different and there is still much in it of great value, not least his measured judgements. ‘Cluny and the First Crusade’ and ‘The three Lives of Odo Arpinus’ are detailed contributions to the study of the First Crusade, while ‘Early crusading in eastern Germany’ considers an important propaganda document of the early twelfth century. ‘Two notes on the Anglo-Flemish crusaders’ and ‘The crusading project of 1150’ add to our knowledge of the Second Crusade and its aftermath. The appendix on ‘The terminology of crusading’ considers the language used to describe crusades and crusaders.

The scholarship is, as is always the case with Constable, impeccable. The range of source material used is very wide and the judgements are weighty and authoritative. Those who read Constable closely can determine what he thinks, but they should never expect strongly expressed opinions from him. His conclusions are always measured and are delivered after a close and impartial consideration of the arguments of others, although his disinclination to commit himself too unequivocally to any interpretative position can be rather disconcerting for those who have been involved in the hurly-burly of the controversies of the last few decades. To put it another way, his achievement in the field of crusade studies has been to open up new topics and provide an authoritative and enlightening introduction to the materials for them. He has left speculation to others.