Few figures from the ancient world have attracted as much speculation, fantasy, and romantic projection as the Druids, the priestly class of the ancient Celtic peoples whose actual nature and history have been obscured by centuries of mythmaking. To ask what we actually know about the Druids is to undertake a necessary act of historical criticism, to separate the genuine evidence from the later accretions, and to arrive at a more realistic, if less romantic, picture of who the Druids really were, what they really did, and what we can and cannot say about them with confidence. The result is a portrait of the Druids and the priestly class that is less idealized than the popular image but, for that very reason, more historically credible and more interesting, and that belongs firmly to the larger context of Celtic religion, mythology, and spirituality.
The Problem of the Evidence
The fundamental challenge in studying the Druids is that they themselves left no written records. According to Julius Caesar, the Druids of Gaul considered it improper to commit their teachings to writing, although they used the Greek alphabet for some purposes, including the keeping of public and private accounts. The information we have about them comes, therefore, from three principal sources, each of which has its own limitations. The first is the testimony of classical Greek and Roman authors, who encountered the Druids in Gaul and Britain during the late Republic and early Empire. The second is the archaeological record of their sanctuaries, ritual equipment, and votive deposits. The third is the medieval manuscript tradition of Ireland, Scotland, and Wales, in which the memory of the older Druidic order was preserved in transformed and often heavily Christianized form.
The classical sources, while they are our most extensive body of evidence, are not without their problems. Caesar, Strabo, Diodorus Siculus, Pomponius Mela, Pliny the Elder, and Tacitus were all writing for Greek or Roman audiences, and they tended to portray the Druids through the lens of Mediterranean cultural categories. They often exaggerated the more exotic or shocking features of Druidic practice, particularly the practice of human sacrifice, in order to make their accounts more interesting to their readers or to score political points against Celtic rivals of Rome. The archaeological record, while it is independent of the literary sources, can be difficult to interpret: many of the objects and monuments that have been associated with the Druids may have had functions that were not exclusively or even primarily religious. The medieval Irish and Welsh sources preserve genuine traditions of the older Druidic order, but they are filtered through centuries of Christian transmission, and it is often difficult to separate the older pagan elements from the later Christian additions.
What the Classical Sources Tell Us
The principal classical source for the Druids is Julius Caesar’s account in his Commentarii de Bello Gallico, written in the 50s BCE after his conquest of Gaul. Caesar’s account, while it is the most extensive, is also the most colored by political considerations, and it should be read with care. According to Caesar, the Druids were a single organized priestly class with a defined hierarchy, a common doctrine, and a long period of training. He claims that they originated in Britain and crossed to Gaul to take up their positions, that they were exempt from military service and from taxation, that they had authority to decide private and public disputes, that they could inflict penalties on those who disobeyed their judgments, and that they were responsible for the education of the young of noble families. He also reports that the Druids considered it improper to commit their teachings to writing, that they taught the immortality of the soul, and that they performed human sacrifice on important occasions.
The other classical sources, while they add details, also confirm the broad picture. Diodorus Siculus, writing in the first century BCE, describes the Druids as philosophers and theologians who taught that the souls of men passed at death into other bodies, and he notes their practice of animal and human sacrifice. Strabo, in his Geographica, mentions the Druids and the related classes of bards and vates, and he notes that the Druids were concerned with natural philosophy and moral teaching as well as with religion. Pomponius Mela, writing in the first century CE, describes the Druids of Gaul as teachers of morality and as interpreters of the will of the gods, and he gives a vivid account of their oak-grove rituals. Tacitus, in his Annals, gives a famous account of the Roman attack on the Druid sanctuary of Anglesey in 60 CE, in which he describes the Druids as they appeared to a Roman army: black-robed figures with their hair cut short, raising their hands to heaven and cursing the Roman invaders.
What Archaeology Tells Us
The archaeological record provides important corroboration of some of the classical accounts and useful correction of others. The votive deposits that have been found in rivers, lakes, and bogs across the Celtic world, including the famous deposits of La Tène metalwork at the type site of La Tène on Lake Neuchâtel, the Snettisham hoard in Norfolk, the Trichtingen hoard in Germany, and many others, attest to the religious practices of the Celtic peoples in the late Iron Age. The sanctuaries that have been excavated, including the great healing sanctuary of Sequana at the source of the Seine, the sanctuary of Sirona at the source of the Moselle, and the many smaller rural sanctuaries scattered across Gaul and Britain, give a picture of the physical settings in which Celtic religious practices were performed.
The human remains that have been found in bogs in northern Europe, including the famous Tollund Man and Grauballe Man in Denmark, the Lindow Man in England, and many others, have been interpreted by some scholars as evidence of human sacrifice, and they have been linked to the Druids by writers who have followed the classical accounts. The interpretation is not without its problems, however, since the bog bodies may have been the victims of execution, of capital punishment, or of various forms of ritual killing that did not necessarily involve the Druids. The fact that the bodies often show signs of violent death and that they have been preserved by the anaerobic conditions of the bog does suggest that some form of ritual killing was practiced, but the connection with the Druids specifically is less certain than the popular accounts often imply.
What the Medieval Sources Tell Us
The medieval Irish and Welsh sources preserve a body of traditions about the Druids that is more extensive, in some respects, than the classical sources, but that is also more difficult to evaluate historically. The early Irish law texts, the saints’ lives, the Mythological cycle tales, the Ulster cycle tales, and the Fenian cycle tales all contain references to the Druids and their activities, and the figure of the Druid is a familiar character in medieval Irish literature. The early Welsh sources, particularly the Mabinogion and the works of the medieval Welsh poets, preserve a similar body of tradition.
The medieval Irish sources describe the Druids as a powerful and well-organized class, with a defined hierarchy, a long period of training, and important political and religious functions. They are shown as prophets, as advisers to kings, as critics of the new Christian religion, and as practitioners of various magical arts. The famous confrontation of Saint Patrick with the Druids at the Hill of Tara, in which Patrick is said to have outwitted and overcome the Druids of the High King, is a paradigm of the way in which the older religious order was displaced by the new, and the various other confrontations of saints with Druids in the early Irish saints’ lives follow a similar pattern. The reality behind these accounts, however, is more complex. The Druids of the medieval Irish sources are not the historical Druids of the Iron Age but a literary construct, shaped by the conventions of the genre and by the religious concerns of the early Christian authors, and they should be read with the same critical care that the classical sources require.
The Romantic Invention of the Druid
The modern image of the Druid, the white-robed, oak-cultivating, mistletoe-cutting philosopher-priest of the British Isles, is largely a product of the late seventeenth, eighteenth, and nineteenth centuries, and it has more to do with the romantic and antiquarian concerns of that period than with the historical Druids. The early modern antiquaries, including John Aubrey, William Stukeley, and Edward Williams (better known as Iolo Morganwg), reconstructed the Druids as the original philosophers and priests of Britain, the wise men of a pre-Christian civilization whose teachings paralleled those of the ancient philosophers of Greece and Rome. The Romantic movement of the late eighteenth and nineteenth centuries, with its enthusiasm for ancient and “primitive” religions, transformed the Druids into idealized figures of priestly wisdom, and the modern Druid orders that began to be founded in the late eighteenth century, including the Ancient Order of Druids and the Order of Bards, Ovates, and Druids, continue to draw on this idealized image.
The historical reality, of course, was very different. The actual Druids, as far as we can tell from the evidence, were not the peaceful philosophers of legend but powerful religious and political leaders, deeply embedded in the social and political life of their societies, and they performed functions that included sacrifice, divination, the enforcement of social norms, and the exercise of political authority. The white robes and the golden sickles of the popular image have very little basis in the historical record, and the mistletoe-cutting ceremony described by Pliny, while it is genuine, is not necessarily representative of Druidic practice as a whole. The historical Druids, in short, are more interesting and more complex than the romantic image suggests, and they deserve to be studied on their own terms, with the evidence for what they were rather than for what we might wish them to have been.
What We Can and Cannot Say
The honest answer to the question of what we know about the Druids is that we know a great deal less than the popular literature suggests, and that much of what we think we know is based on sources that are themselves problematic. We can say with reasonable confidence that the Druids were a class of religious specialists who existed in the Celtic world from at least the fourth century BCE until the gradual disappearance of the order under Roman and Christian pressure. We can say that they performed important religious, judicial, and educational functions in their societies. We can say that they were concerned with the natural world, with the calendar, with the interpretation of omens, and with the performance of sacrifice. We can say that they played an important role in the political life of their communities, advising kings and serving as judges and intermediaries between tribes.
What we cannot say with the same confidence is much about their actual religious doctrines, since the classical sources are too brief and too colored by Mediterranean categories to give us a clear picture, and the medieval sources are too heavily Christianized to be reliable guides. We cannot say with certainty how the Druidic order was organized, since the classical accounts differ on this point and the archaeological evidence is too sparse to be definitive. We cannot say with any precision what the training of a Druid actually involved, although the classical sources agree that it was long and demanding. And we cannot say with any confidence what the actual beliefs of the Druids were about the soul, the afterlife, or the nature of the divine, although the broad outlines of their teachings can be reconstructed from the converging testimony of the various sources. The honest scholar of the Druids, in other words, must be content with a partial and provisional picture, and must be willing to acknowledge the limits of what we know, as well as the value of what we can reasonably infer.