Some writers have tried to draw a distinction between the Druids of Gaul and of Ireland, especially in the matter of their priestly functions.1014 But, while a few passages in Irish texts do suggest that the Irish Druids were priests taking part in sacrifices, etc., nearly all passages relating to cult or ritual seem to have been deliberately suppressed. Hence the Druids appear rather as magicians—a natural result, since, once the people became Christian, the priestly character of the Druids would tend to be lost sight of. Like the Druids of Gaul, they were teachers and took part in political affairs, and this shows that they were more than mere magicians. In Irish texts the word "Druid" is somewhat loosely used and is applied to kings and poets, perhaps because they had been pupils of the Druids. But it is impossible to doubt that the Druids in Ireland fulfilled functions of a public priesthood. They appear in connection with all the colonies which came to Erin, the annalists regarding the priests or medicine-men of different races as Druids, through lack of historic perspective. But one fact shows that they were priests of the Celtic religion in Ireland. The euhemerised Tuatha Dé Danann are masters of Druidic lore. Thus both the gods and the priests who served them were confused by later writers. The opposition of Christian missionaries to the Druids shows that they were priests; if they were not, it remains to be discovered what body of men did exercise priestly functions in pagan Ireland. In Ireland their judicial functions may have been less important than in Gaul, and they may not have been so strictly organised; but here we are in the region of conjecture. They were exempt from military service in Gaul, and many joined their ranks on this account, but in Ireland they were "bonny fechters," just as in Gaul they occasionally fought like mediæval bishops.1015 In both countries they were present on the field of battle to perform the necessary religious or magical rites.
Since the Druids were an organised priesthood, with powers of teaching and of magic implicitly believed in by the folk, possessing the key of the other-world, and dominating the whole field of religion, it is easy to see how much veneration must have been paid them. Connoting this with the influence of the Roman Church in Celtic regions and the power of the Protestant minister in the Highlands and in Wales, some have thought that there is an innate tendency in the Celt to be priest-ridden. If this be true, we can only say, "the people wish to have it so, and the priests—pagan, papist, or protestant—bear rule through their means!"
Thus a close examination of the position and functions of the Druids explains away two popular misconceptions. They were not possessed of any recondite and esoteric wisdom. And the culling of mistletoe instead of being the most important, was but a subordinate part of their functions.
In Gaul the Roman power broke the sway of the Druids, aided perhaps by the spread of Christianity, but it was Christianity alone which routed them in Ireland and in Britain outside the Roman pale. The Druidic organisation, their power in politics and in the administration of justice, their patriotism, and also their use of human sacrifice and magic, were all obnoxious to the Roman Government, which opposed them mainly on political grounds. Magic and human sacrifice were suppressed because they were contrary to Roman manners. The first attack was in the reign of Augustus, who prohibited Roman citizens from taking part in the religion of the Druids.1016 Tiberius next interdicted the Druids, but this was probably aimed at their human sacrifices, for the Druids were not suppressed, since they existed still in the reign of Claudius, who is said to have abolished Druidarum religionem dirae immanitatis.1017 The earlier legislation was ineffective; that of Claudius was more thorough, but it, too, was probably aimed mainly at human sacrifice and magic, since Aurelius Victor limits it to the "notorious superstitions" of the Druids.1018 It did not abolish the native religion, as is proved by the numerous inscriptions to Celtic gods, and by the fact that, as Mela informs us, human victims were still offered symbolically,1019 while the Druids were still active some years later. A parallel is found in the British abolition of S=ati in India, while permitting the native religion to flourish.
Probably more effective was the policy begun by Augustus. Magistrates were inaugurated and acted as judges, thus ousting the Druids, and native deities and native ritual were assimilated to those of Rome. Celtic religion was Romanised, and if the Druids retained priestly functions, it could only be by their becoming Romanised also. Perhaps the new State religion in Gaul simply ignored them. The annual assembly of deputies at Lugudunum round the altar of Rome and Augustus had a religious character, and was intended to rival and to supersede the annual gathering of the Druids.1020 The deputies elected a flamen of the province who had surveillance of the cult, and there were also flamens for each city. Thus the power of the Druids in politics, law, and religion was quietly undermined, while Rome also struck a blow at their position as teachers by establishing schools throughout Gaul.1021
M. D'Arbois maintains that, as a result of persecution, the Druids retired to the depths of the forests, and continued to teach there in secret those who despised the new learning of Rome, basing his opinion on passages of Lucan and Mela, both writing a little after the promulgation of the laws.1022. But neither Lucan nor Mela refer to an existing state of things, and do not intend their readers to suppose that the Druids fled to woods and caverns. Lucan speaks of them dwelling in woods, i.e. their sacred groves, and resuming their rites after Cæsar's conquest not after the later edicts, and he does not speak of the Druids teaching there.1023 Mela seems to be echoing Cæsar's account of the twenty years' novitiate, but adds to it that the teaching was given in secret, confusing it, however, with that given to others than candidates for the priesthood. Thus he says: "Docent multa nobilissimos gentis clam et diu vicenis annis aut in specu aut in abditis saltibus,"1024 but there is not the slightest evidence that this secrecy was the result of the edicts. Moreover, the attenuated sacrificial rites which he describes were evidently practised quite openly. Probably some Druids continued their teaching in their secret and sacred haunts, but it is unlikely that noble Gauls would resort to them when Greco-Roman culture was now open to them in the schools, where they are found receiving instruction in 21 A.D.1025 Most of the Druids probably succumbed to the new order of things. Some continued the old rites in a modified manner as long as they could obtain worshippers. Others, more fanatical, would suffer from the law when they could not evade its grasp. Some of these revolted against Rome after Nero's death, and it was perhaps to this class that those Druids belonged who prophesied the world-empire of the Celts in 70 A.D.1026 The fact that Druids existed at this date shows that the proscription had not been complete. But the complete Romanising of Gaul took away their occupation, though even in the fourth century men still boasted of their Druidic descent.1027
The insular Druids opposed the legions in Southern Britain, and in Mona in 62 A.D. they made a last stand with the warriors against the Romans, gesticulating and praying to the gods. But with the establishment of Roman power in Britain their fate must have resembled that of the Druids of Gaul. A recrudescence of Druidism is found, however,