Merlin the prophet and magician is instantly recognizable to modern readers well beyond the confines of medieval studies. However, Anne Lawrence-Mathers's book traces a comparatively neglected aspect of his story. She reminds us that Merlin was more than an important figure in medieval literature, playing a key role in the many romances of King Arthur and the Grail. For many medieval chroniclers, he was also a historical figure who had a place in histories and chronicles from the twelfth to the fifteenth centuries alongside other figures from early British history who were accepted as real. Lawrence-Mathers argues that this “historical” Merlin was presented as a prophet, astrologer, and magician, but he was significantly different from the more flamboyant and powerful Merlin of romance.

Because its focus is on the Merlin whom medieval chroniclers presented as a real historical figure, Lawrence-Mathers's book does not trace in detail either the development of the Celtic Merlin legend before the twelfth century or the representations of Merlin in medieval or modern literature (although some key literary works such as the romances of Robert de Boron are discussed). More information about both of these topics can be found in another recent study, Stephen Knight's Merlin: Knowledge and Power through the Ages (Cornell University Press, 2009). Instead, Lawrence-Mathers sets Merlin and his activities firmly in their historical context, exploring why Merlin's story was taken up by twelfth-century historians and where his activities and powers fit into medieval ideas about magic, astrology, and demons. By doing so, she allows us to see how Merlin could have been seen as a credible historical figure and shows why his story was so appealing to later writers.

The book starts by discussing the Merlin who appeared on the British and European historical scene in the twelfth century in Geoffrey of Monmouth's History of the Kings of Britain, which included a smaller and perhaps earlier work, the Prophecies of Merlin. Lawrence-Mathers discusses the reasons for the spectacular success of Geoffrey's History, arguing that it was written at just the right time to provide a new national narrative for the new Anglo-Norman aristocracy who did not identify with older histories of the English. She also suggests that Merlin's prophecies may themselves have contributed to the popularity of Geoffrey's History: during the political instability of the 1130s to 1150s, their potential to explain the present and offer insight into the future proved highly attractive.

Later chapters explore various aspects of Merlin as they appear in later chronicles: his prophecies, his astrology, his magic, and the legend that his father was a demon. Lawrence-Mathers compares these depictions of Merlin with what we know about attitudes toward medieval magic, astrology, and prophecy more broadly, to show that Merlin's prophecies were taken seriously and elaborated on into the fifteenth century and beyond. She also argues that much of Merlin's magic and astrology would probably have been regarded as “natural magic”: that is, they were thought to be based on Merlin's superior knowledge and ability to manipulate mysterious natural forces, and not on trafficking with demons. Merlin was therefore not a demonic magician but an intellectual who used new, sophisticated scientific knowledge to achieve marvellous effects. This Merlin had considerable appeal in a time when intellectuals and aristocrats were interested in astrology and natural magic, and in their potential to shed light on political events, as the survival of political horoscopes from twelfth-century England shows. However, things were not always so simple. The legend that Merlin's father had been a demon aroused anxiety in some chroniclers, and it was not easy to explain all his powers as natural magic. Merlin therefore remained a figure close to the borderline between what was acceptable and what was condemned, and when attitudes toward magic and astrology hardened in the later Middle Ages, this led to some much more negative depictions of him. It might have been interesting, too, to set Merlin in the context of the wider interest in “marvels” in twelfth-century historical writing as discussed by C. S. Watkins in History and the Supernatural in Medieval England (Cambridge, 2007). Nevertheless, there is a great deal here to interest historians of medieval literature and courtly culture, as well as historians of magic and astrology. Lawrence-Mathers brings together chronicles and literary works with what we know about the reality of magic and astrology in medieval courts very successfully.

This book is written for a popular audience as well as an academic one. Indeed, it succeeds admirably in addressing both markets: it is enjoyable to read and written in a very accessible style, but at the same time it includes enough references to lead interested readers to the primary sources and other secondary works, and contains much new information for scholars. It deserves to attract attention from a wide readership.