Druidry, or Druidism, is the religion of the Druids, a pagan Celtic priesthood that existed in France, Britain and Ireland before the coming of Christianity to those lands. Its international headquarters was on the island of Mona, now called Anglesey, off the north-west coast of Wales, but was destroyed by the Romans in 61 AD during the revolt of Boudica.
Druid beliefs, as recorded by Julius Caesar, revolved around observations of the motions of the heavenly bodies and their influences on the earth, as in astrology, and they were also firm believers in reincarnation, so much that it was possible to defer the payment of debts until the next life. Caesar recounted stories of the Druids sacrificing criminals and enemy soldiers captured in battle in huge wicker men by burning them to death. These stories should be taken with a grain of salt as Caesar was known for embellishing stories of his time in Gaul.
The two privileged classes are the Druids and the knights. The Druids officiate at the worship of the gods, regulate public and private sacrifices, and give rulings on all religious questions. Large numbers of young men flock to them for instruction, and they are held in great honour by the people. They act as judges in practically all disputes, whether between tribes or between individuals; when any crime is committed, or a murder takes place, or a dispute arises about an inheritance or a boundary, it is they who adjudicate the matter and appoint the compensation to be paid and received by the parties concerned. Any individual or tribe failing to accept their award is banned from taking part in sacrifice - the heaviest punishment that can be inflicted upon a Gaul. Those who are laid under such a ban are regarded as impious criminals. Everyone shuns them and avoids going near or speaking to them, for fear of taking some harm by contact with what is unclean; if they appear as plaintiffs, justice is denied them, and they are excluded from a share in any honour. All the Druids are under one head, whom they hold in the highest respect. On his death, if any one of the rest is of outstanding merit, he succeeds to the vacant place; if several have equal claims, the Druids usually decide the election by voting, though sometimes they actually fight it out. On a fixed date in each year they hold a session in a consecrated spot in the country of the Carnutes, which is supposed to be the centre of Gaul. Those who are involved in disputes assemble here from all parts, and accept the Druids' judgements and awards. The Druidic doctrine is believed to have been found existing in Britain and thence imported into Gaul; even today those who want to make a profound study of it generally go to Britain for the purpose. Julius Caesar’s The Conquest of Gaul, book VI.
Druidic training was very hard, and involved spending 20 years learning by heart thousands of lines of poetry and song, which included being placed under a rock in a river in order to recite them. If the postulant survived this ordeal he or she became a 'bard', the lowest grade of Druid. The next grade was 'ovate' (meaning seer), and then came Druid proper.
The Romans attempted to suppress Druidism but it survived into Christian times when a certain amount of assimilation took place. Many Christian churches in the British Isles were built on the site of Druidic temples, especially those dedicated to the dragon-slaying saints Michael and George. It is also believed that the wizard Merlin, companion to King Arthur, was a Druid.
Druidism survived in remote areas of Wales until the 18th century, when it was revived in a new popular form by John Toland and others, who founded the first of the modern Druid orders in 1717. Modern Druids have dispensed with many of their ancient beliefs and practices and in many ways resemble Freemasonry. They congregate at Stonehenge on the summer solstice to enact their ceremonies.