This is a study of a medieval historian and what he had to say. It is the fruit of a collaboration originally conceived almost ten years ago and has taken far longer to complete than it should. The distance between Cardiff and London, Ontario, and our other commitments, provide excuses, albeit rather feeble ones. More seriously, we found that the price of being engaged on a genuinely collaborative undertaking was that our labour was increased rather than diminished as points of detail were thrashed out and drafts passed to and fro across the Atlantic.

Work was already well advanced when Professor Robert Huygens' new edition of William of Tyre's history was published. It is difficult for us to express adequately our indebtedness to him for what has proved to be of enormous assistance in the final stages of our research.

Appreciation and thanks for their generous help in many different ways and at widely differing stages of our work are due to many people, not least: Dr D. R. Bates, Miss J. Buckingham, Mr Ceri Davies, Professor R. B. C. Huygens, Dr C. H. Knowles, Professor J. R. Lander, Professor J. S. C. Riley-Smith, the late Dr R. C. Smail, and Professor W. H. Stockdale; also the staff of the Bodleian Library, Oxford and the libraries at University College Cardiff and the University of Western Ontario, where in particular we would mention Dr R. E. Lee, the chief librarian, and his colleagues Mr R. Gardiner and Mr G. Malcahy.