English Castles was first published in 1954 and rapidly established itself as the classic introduction to the subject. Firmly based on documentary and archaeological sources, as well as extensive field work by the author, English Castles surveyed the whole subject of the rise, heyday and decline of medieval castles in England and, despite its title, Wales with a breadth and lucidity that continue to command respect. When Allen Brown first wrote the book, there were few others working in the field. Much published work on castle history, despite earlier authors such as Allen's favourite Mrs E.S. Armitage, tended to owe more to sometimes over-romanticised myth and legend than to hard historic facts and field observation. There were of course exceptions to this general rule, such as the famous Ministry of Works ‘blue guides’ with their measured prose and carefully dated plans. These pioneered the scholarly, academic approach to the history, architecture and description of individual monuments in the care of the State. However, it has to be said that meticulous scholarship did not always equate with readability and many of the blue guides were early casualties of a later, less learned and more populist regime not so interested in rich text and dated plans. Allen's book introduced the subject to a public which wanted the wider picture and whose appetite had probably been whetted by visits to individual castles. The popularity of English Castles was such that a revised paperback edition followed in 1962 – I still possess my copy bought as an undergraduate for five shillings. In 1976, a new and quite extensively revised edition was published. It says much for Allen's original scholarship and research that the core of the book was still substantially his work of twenty years before. Nevertheless, in the intervening years there had been a remarkable growth in castle studies, as Allen acknowledged in his Preface to the new edition. He rightly drew attention to the publication of the medieval volumes of the History of the King's Works, but with characteristic modesty omitted to mention that he was one of the three authors of this seminal work. He also highlit new research, sponsored by the Royal Archaeological Institute, on the origins of castles. All this new information, which in many cases amplified and confirmed much of Allen's original text, was woven seamlessly into the new edition.