A druid was a member of the important religious group in ancient Celtic cultures. Druids were religious leaders, judges, keepers of knowledge, doctors, and advisors to leaders. They did not write down their own records. Although they were known to be able to read and write, they were not allowed by their beliefs to write their knowledge. Other cultures, like the Romans and Greeks, described their beliefs and practices in detail.
The first written mentions of druids date back to the 4th century BCE. The most detailed early description comes from Julius Caesar’s book, Commentarii de Bello Gallico, written in the 50s BCE. Other Roman writers, such as Cicero, Tacitus, and Pliny the Elder, also wrote about druids. After the Romans took over Gaul, the Roman government, under emperors Tiberius and Claudius in the 1st century CE, stopped druids from working. By the 2nd century, there were no more written records about druids.
In about 750 CE, the word druid appeared in a poem by Blathmac, who wrote about Jesus, saying Jesus was "better than a prophet, more knowledgeable than every druid, a king who was a bishop and a complete sage." Druids are mentioned in stories from Irish mythology, first written by monks and nuns of the Celtic Church, such as Táin Bó Cúailnge (written in the 12th century). Later Christian stories often showed druids as wizards who resisted the spread of Christianity. During the 18th and 19th centuries, when interest in Celtic culture grew, new religious and spiritual groups formed based on ideas about ancient druids, called Neo-Druidism. Many common beliefs about druids, based on old misunderstandings, have been replaced by more recent research.
Etymology
The English word "druid" comes from the French word "druide," which in turn comes from the Latin word "druida" (found only in the plural form "druides"). This Latin word is believed to have been borrowed from the Gaulish language, which used the form "druid-." The Old English word "drȳ," meaning a magician or wizard, was borrowed from Celtic languages, possibly from Irish or Brythonic.
The Gaulish word "druides" is related to the Old Irish word "druí" (plural "druíd," meaning "magician" or "wizard") and may also be connected to the Middle Welsh word "dryw," meaning "seer" (as found in the Book of Taliesin). In both Irish and Welsh, "druí" and "dryw" could sometimes refer to the wren, a bird believed to have prophetic powers in these traditions. The Middle Welsh word "derwydd" (meaning "seer") and the Old Breton word "dorguid" (meaning "prophetic" or "magical") show similar patterns. These may reflect changes in how the Proto-Celtic word "dru-wid-" was formed, possibly based on the Celtic word "daru-" meaning "oak tree," or from "*do-are-wid-" meaning "who sees beyond."
All these forms are believed to come from a Proto-Celtic noun reconstructed as "dru-wid-s" (plural "dru-wid-es"). The second part of the word is generally linked to the Proto-Indo-European (PIE) verb "weyd-" meaning "to see" or "to know." The origin of the first part has been debated by scholars. Most believe it comes from the PIE root "derw-" (or "*dru-") meaning "oak tree," which also metaphorically meant "strong" or "firm." Based on this, the compound word has been interpreted as "oak-knower," "someone who knows about trees," or "someone with strong insight." This connection was noted by the Roman writer Pliny in the 1st century, who compared the first part to the Greek word "drŷs" meaning "oak." Some scholars, however, suggest the first part might be an intensive prefix, giving the meaning "very wise."
Practices and doctrines
Ancient and medieval writers provide information about the religious duties and social roles of druids.
Greco-Roman and Irish sources agree that druids were important in pagan Celtic society. Julius Caesar wrote that druids were one of the two most important groups in the region (alongside the nobles) and were responsible for organizing worship, sacrifices, divination, and legal matters in Gallic, British, and Irish societies. He noted that druids were not required to serve in the military or pay taxes and had the power to exclude people from religious events, making them outcasts. Diodorus Siculus and Strabo also wrote that druids were respected and could stop battles if they intervened between armies.
Diodorus described druids as "philosophers" and "learned in religious matters." Strabo said their knowledge included natural and moral philosophy, while Ammianus Marcellinus listed them as people who studied "obscure and profound subjects." Pomponius Mela was the first to mention that druidic education was secret and took place in caves and forests. Cicero wrote about a Gaulish druid who claimed to understand nature as the Greeks called it "physiologia" and used augury and guessing to make predictions.
Druidic knowledge was memorized through many verses, and Caesar noted it could take up to twenty years to learn. No ancient verses from druidic teachings are known to have survived. Instruction was oral, but the Gauls used a written language with Greek letters for daily use. By Caesar’s time, inscriptions had shifted to Latin script.
Caesar believed the druids kept their knowledge secret to protect it and improve their memory. He wrote that many young men studied with druids, and some chose this path, while others were sent by their families.
Greek and Roman writers often described druids as practicing human sacrifice. Caesar said criminals were preferred as victims, but innocent people were used if criminals were unavailable. One method involved burning victims alive inside a wooden effigy, now called a "wicker man." A 10th-century text, Commenta Bernensia, mentioned sacrifices to gods like Teutates, Esus, and Taranis through drowning, hanging, and burning.
Diodorus Siculus wrote that druids acted as intermediaries between people and gods during sacrifices. He described how druids used bird behavior and animal sacrifices to predict the future. In important matters, they used human victims, observing their movements and blood to read omens.
Archaeological findings in western Europe, such as mass graves in Gaul, have been linked to Iron Age human sacrifices. Some experts, like Jean-Louis Brunaux, believed these were sacrifices to a war god, while others, like Martin Brown, thought they were honored warriors buried in sanctuaries. Some historians question whether Roman and Greek writers accurately described druids, suggesting these claims might reflect Roman bias against foreign cultures.
Nora Chadwick, an expert in medieval literature, argued druids were philosophers and not involved in human sacrifice, calling such claims Roman propaganda. Alexander Cornelius Polyhistor described druids as philosophers who taught the immortality of the soul and reincarnation, similar to the Pythagorean belief.
Julius Caesar wrote that druidic education focused on teaching the immortality of the soul, which helped people face death without fear. He also noted studies on stars, geography, natural philosophy, and religion.
Diodorus Siculus, writing in 36 BCE, said druids followed the Pythagorean idea that souls are immortal and reincarnate after a set time. In 1928, Donald A. Mackenzie suggested Buddhist missionaries from India might have influenced druidic beliefs. Caesar mentioned the druidic belief that the tribe’s ancestor was a god called "Dispater," meaning "Father Dis."
Diogenes Laertius, writing in the 3rd century CE, wrote that druids used riddles and sayings to teach respect for the gods, discourage harm, and promote strong behavior.
Druids in mythology
Druids are important figures in Irish folklore, often serving as religious advisors and counselors to kings and lords. They were believed to have special powers, such as the ability to predict the future. One well-known example was Cathbad, the chief druid in the court of King Conchobar mac Nessa of Ulster. Cathbad appears in many stories, most of which describe his ability to foresee events. In the tale of Deirdre of the Sorrows, a key character in the Ulster Cycle, Cathbad told the court that Deirdre would grow up to be very beautiful. He also warned that kings and lords would fight over her, causing much bloodshed, and that Ulster's three greatest warriors would be forced into exile because of her. The king ignored this prophecy, but it eventually came true.
Another important druid was Amergin Glúingel, a bard and judge for the Milesians in the Mythological Cycle. The Milesians wanted to take control of Ireland from the Tuatha Dé Danann. As the Milesians approached, the druids of the Tuatha Dé Danann created a magical storm to stop their ships from landing. Amergin then called upon the spirit of Ireland, reciting a powerful chant known as The Song of Amergin. After successfully landing, he helped divide the land among his royal brothers during the conquest of Ireland, earning the title Chief Ollam of Ireland.
Other notable druids from Irish mythology include Tadg mac Nuadat, a character from the Fenian Cycle, and Mug Ruith, a blind druid from Munster known for his great power.
Female druids
In Irish mythology, there are many female druids who have important roles in culture and religion, similar to their male counterparts. The Irish language has several names for female druids, such as bandruí ("woman-druid"), mentioned in stories like Táin Bó Cúailnge. Another is Bodhmall, who appears in the Fenian Cycle, a group of tales about the hero Fionn mac Cumhaill. Tlachtga is the daughter of the druid Mug Ruith and is linked to the Hill of Ward, a place where festivals were held in her honor during the Middle Ages.
Bandruí is also the name of Biróg, a druid from the Tuatha Dé Danann, who plays a key role in a folktale. In this story, the Fomorian warrior Balor tries to stop a prophecy that says he will be killed by his grandson. To do this, he imprisons his daughter Eithne on Tory Island to keep her away from men. Bé Chuille, the daughter of the woodland goddess Flidais, appears in a tale from the Metrical Dindshenchas. She joins other Tuatha Dé members to defeat the evil Greek witch Carman. Other bandrúi include Relbeo, a Nemedian druid from The Book of Invasions, who is described as the daughter of the king of Greece and the mother of Fergus Lethderg and Alma One-Tooth. Dornoll, a bandrúi in Scotland, trained warriors like Laegaire and Conall. She was the daughter of Domnall Mildemail.
Classical writers mention the Gallizenae (or Gallisenae), priestesses who remained virgins and lived on the island of Île de Sein near Pointe du Raz in western Brittany. The Greek geographer Artemidorus Ephesius and the historian Strabo wrote about them, noting that their island was closed to men, but the women visited the mainland to meet their husbands. Pomponius Mela described the Gallizenae as both advisors and healers. He wrote that they were believed to have special powers, such as controlling the sea and wind, changing into animals, curing diseases, and predicting the future. They only helped travelers who sought their guidance.
According to The Historia Augusta, the Roman emperor Alexander Severus received a prophecy about his death from a Gallic druidess (druiada). The text also mentions that the emperor Aurelian asked druidesses about the future of his descendants, and they predicted that Claudius II would succeed him. Flavius Vopiscus wrote that the emperor Diocletian received a prophecy from a druidess of the Tungri people.
Sources on druid beliefs and practices
The earliest written records about druids come from ancient Greece and Rome. Archaeologist Stuart Piggott compared how these ancient writers viewed druids to how Europeans in the 15th and 18th centuries saw societies in places like the Americas and the South Sea Islands. He noted that both groups believed these societies had less technology and were less advanced in their political systems.
Historian Nora Chadwick divided the ancient descriptions of druids into two groups, based on how they were written and the time periods they described. She called the first group the "Posidonian" tradition, named after the writer Posidonius. This group criticized the Iron Age societies of Western Europe, calling them "barbaric." The second group, called the "Alexandrian" tradition, was influenced by scholars in Alexandria, Egypt. This group showed more respect and admiration for these foreign cultures. Piggott linked this division to ideas called "hard primitivism" and "soft primitivism," studied by historians Arthur Oncken Lovejoy and Franz Boas.
Some scholars believe the ancient accounts of druids are unreliable and may be fictional. They suggest that druids were made up by Roman and Greek writers to describe the "barbaric" people outside their world, which helped justify Roman expansion into those regions.
The earliest known records of druids come from two Greek texts written around 300 BCE: one by Sotion of Alexandria, a history of philosophy, and another by Aristotle, a study of magic. These texts are lost, but they were quoted in a 2nd-century CE work called Vitae by Diogenes Laërtius.
In Vitae, it is written that philosophy may have started with people from other cultures. It mentions groups like the Magi in Persia, the Chaldaei in Babylon or Assyria, the Gymnosophistae in India, and the druids among the Celts and Gauls. These groups were described by Aristotle and Sotion.
Greek and Roman texts from the 3rd century BCE mention "barbarian philosophers," possibly referring to the Gaulish druids.
The first detailed description of druids comes from Julius Caesar’s Commentarii de Bello Gallico, written in the 50s or 40s BCE. As a Roman general planning to conquer Gaul and Britain, Caesar described druids as people who performed religious rituals, sacrifices, and interpreted spiritual matters. He said they were one of the two respected classes in Gaul, along with the equites (a privileged class in Rome). They also acted as judges.
Caesar wrote that druids followed a single leader until his death, after which a new leader was chosen by voting or conflict. He noted that they met yearly at a sacred place in the territory of the Carnutes, believed to be the center of Gaul. They saw Britain as the heart of druidic learning and said druids were not found among German tribes east of the Rhine. Caesar claimed that young men trained for years to become druids, memorizing religious teachings. He wrote that their main belief was that souls do not die but move to new bodies. They studied stars, the cosmos, nature, and the gods, showing knowledge of astronomy and religion. Caesar also said druids oversaw rituals involving human sacrifices, usually of criminals, burned inside a wicker man.
Modern historians criticize Caesar’s account as possibly inaccurate. Some, like Fustel de Coulanges, pointed out that Caesar never mentioned druids in his writings about conquering Gaul, nor did Aulus Hirtius, who continued Caesar’s work. Historian Ronald Hutton argued that Caesar portrayed druids as both civilized (knowledgeable and religious) and barbaric (practicing human sacrifice) to make them seem worthy of inclusion in the Roman Empire but in need of Roman rule. Others, like Sean Dunham, suggested Caesar compared druids to Roman senators. Daphne Nash believed Caesar exaggerated the centralization of druid leadership and their connection to Britain.
Other historians think Caesar’s account might be more accurate. Norman J. DeWitt suggested Caesar described an idealized version of druid society from the 2nd century BCE, before major conflicts changed Gaul. John Creighton noted that druids in Britain may have already been losing influence by the mid-1st century BCE. Miranda Aldhouse-Green (2010) argued Caesar’s descriptions are the most detailed and reliable about druids, even if he may have exaggerated some details to support Roman expansion.
Other ancient writers, like Cicero, also wrote about druids. Cicero met a Gallic druid named Divitiacus of the Aedui tribe, who was knowledgeable about nature and practiced augury (interpreting omens). However, it is unclear if Divitiacus was truly a druid, as Caesar never called him one and described him as a political leader instead.
Another writer, Diodorus Siculus, wrote about druids in his Bibliotheca Historica (36 BCE). He called them drouidas and described them as philosophers and theologians, along with poets and singers.
Archaeology
As historian Jane Webster noted, "individual druids … are unlikely to be identified through archaeology." A.P. Fitzpatrick studied what he thought were symbols related to the stars on swords from the late Iron Age. He found it difficult to connect any physical objects, such as the Coligny calendar, to druidic culture.
Some archaeologists have tried to connect discoveries with written records about druids. Anne Ross linked evidence of human sacrifice in Celtic society, such as the Lindow Man bog body, to Roman and Greek writings that described druids overseeing such rituals. Miranda Aldhouse-Green, a professor at Cardiff University, pointed out that Suetonius’s army would have traveled near the Lindow Man’s location while dealing with Boudicca. She suggested the sacrifice might be connected to this event. A 1996 discovery of a skeleton buried with medical tools and possibly religious items was later called the "Druid of Colchester."
In Deal, Kent, an excavation uncovered the "Deal Warrior," a man buried around 200–150 BCE with a sword, shield, and a rare headband. The headband was made of bronze, with a wide band around the head and a thin strip across the top. Hair traces on the metal showed it was worn directly on the head, without padding. The design of the headdress resembles images of priests from the Romano-British period centuries later. This has led some archaeologists to suggest the man might have been a religious official, possibly a druid.
History of reception
During the Gallic Wars from 58 to 51 BCE, the Roman army, led by Julius Caesar, conquered the tribal chiefdoms of Gaul and added the region to the Roman Republic. Later records describe how the Romans introduced laws to remove druids from Gaul. Pliny the Elder, writing in the 70s CE, stated that Emperor Tiberius (ruled 14–37 CE) passed laws banning druidic practices and other native soothsayers and healers. Pliny believed this would end human sacrifice in Gaul. Suetonius, writing in the 2nd century CE, noted that Emperor Augustus (ruled 27 BCE–14 CE) made it illegal for someone to be both a druid and a Roman citizen. Later, Emperor Claudius (ruled 41–54 CE) passed a law that "thoroughly suppressed" druids by banning their religious practices.
The strongest evidence of druidic traditions in the British Isles comes from the Celtic word druwid-, which appears in Old Irish as druídecht (meaning "magic") and in Welsh as dryw (meaning "seer").
The druids, as a priestly group, disappeared in Wales after the region converted to Christianity by the 7th century. However, roles such as bards and seers (Welsh: dryw) remained in medieval Wales until the 13th century.
In 1764, Minister Macauley reported finding five druidic altars, including a large circle of stones standing upright in the ground near Stallir House on Boreray, near the UK’s westernmost settlement, St. Kilda.
Classics professor Phillip Freeman wrote about a 4th-century CE text, the Historia Augusta, which mentions three references to "dryades" (translated as "druidesses") in Roman Gaul. Freeman noted that these women may not have been direct descendants of druids but showed that prophecy remained among Gaulish people. Female druids also appear in later Irish myths, such as the legend of Fionn mac Cumhaill, who was raised by the druid Bodhmall and another wise woman.
The story of Vortigern, as recorded by Nennius, describes how the British leader invited twelve druids to help him after being excommunicated by Germanus of Auxerre.
In religious texts, druids are often shown as magicians or diviners. In the life of Saint Columba, two druids taught the daughters of Lóegaire mac Néill, the High King of Ireland, and tried to stop Saint Patrick and Columba by creating clouds and mist. Before the 561 CE Battle of Culdremne, a druid created a protective barrier around an army, though the exact meaning of the term used is unclear. Irish druids had a unique hairstyle, and the word druí was used to describe magus (a wise person). In one passage, Saint Columba referred to Jesus as his druid. A story about Saint Beuno mentions that when he died, he saw "all the saints and druids."
Sulpicius Severus wrote about Saint Martin of Tours encountering a funeral where a body was carried in a winding sheet. Martin mistook this for druidic rituals and used his cross to stop the procession. The people became stiff and spun in place before Martin allowed them to continue.
In the 18th century, interest in druids grew in England and Wales. John Aubrey was the first to incorrectly link Stonehenge and other ancient monuments to druids. William Stukeley later popularized this idea. John Toland is often wrongly credited with founding the Ancient Druid Order, but historian Ronald Hutton found that the order was actually created by George Watson MacGregor Reid in 1909. The order never used the title "Archdruid" and falsely claimed William Blake was its "Chosen Chief" from 1799 to 1827, despite no evidence in Blake’s work. Blake’s ideas were influenced by other sources, not druids. Toland was inspired by Aubrey’s theories but did not credit him. The role of bards in 10th-century Wales was established by Hywel Dda, and the idea that druids were their predecessors arose in the 18th century.
In the 19th century, some people believed druids were the main resistance group among the Gauls during the Roman conquest, based on the Gallic Wars. This idea was later dismissed by scholars but still appears in folk history.
Druids became more common in popular culture during the Romanticism movement. In 1809, Chateaubriand’s novel Les Martyrs told the story of a druid priestess and a Roman soldier. In 1817, an opera in Trieste, La Sacerdotessa d'Irminsul, featured a druid priestess. Vincenzo Bellini’s opera Norma was a failure in Milan but became a hit in London in 1833. The opera reused elements from earlier works, including themes of love and duty. The character of Norma was inspired by the moon goddess worshipped in the "grove of the Irmin statue."
A key figure in the 19th-century revival of druidic ideas was Edward Williams, known as Iolo