The druids were the priests of the ancient Celts, but their role and authority in Celtic society was so much more than just presiding over religious ceremonies. They were also teachers, scientists, historians, healers, and judges. We know about the druids from ancient authors like the Roman general Julius Caesar and the Greek philosopher Posidonius, but also from medieval Irish stories.

Although we don’t know everything we would like about the druids, the information we do possess is fascinating. For example, the druids believed passionately in reincarnation, were highly organized, and included many women among their numbers. Modern misconceptions about the druids are common. They did not in fact worship trees or engage in frequent human sacrifice. There are certainly some aspects of druidic behavior that will strike readers as cruel and barbaric, but we should see them in the context of the entire belief system of the druids and realize that they lived in a world very different from our own.

By the end of the first century CE the Romans had conquered all the Celtic lands except Ireland and the northernmost parts of Britain. There the old ways of the Celts and druids thrived until the coming of Christianity in the fifth century CE.