All what we know about druids comes almost exclusively from Caesar and that is tantalizing little. For instance we know nothing about their teachings, as this was orally transmitted. In this respect they resemble the Hindu Brahmins, who also transmitted the Vedas orally, but unlike Brahmins, they were not a closed group, but they were recruited from the nobiles. In his De Bello Gallico Caesar is constantly justifying the subjection of Gaul by referring to the barbaric state of living there. Look for instance how he describes the condition of the common people: they were treated as slaves. The implicit message is that he has done a good job. In vi.15 he even states that before his intervention the Gallic nobiles were constantly at with each other: Hi, cum est usus atque aliquod bellum incidit (quod fere ante Caesaris adventum quotannis accidere solebat, uti aut ipsi iniurias inferrent aut illatas propulsarent), omnes in bello versantur. (These, when there is occasion and any war occurs (which before Caesar's arrival was for the most part wont to happen every year, as either they on their part were inflecting injuries or repelling those which others inflected on them), are all engaged in war.) What Caesar is claiming, is that he brought civilization to Gaul. This sounds hauntingly modern, as with such claims the possession of colonies was justified, not to speak of the bringing of democracy to certain countries. That his civilizing process must have cost the lives of hundred thousands of Gallic men, women and children is a minor detail.
These passages are nevertheless important for our knowledge of the social position of Druids and their belief in transmigration. Regarding the latter, it is very difficult to estimate what exactly this belief contained, but I don’t think we must have the Indian idea of dharma and karma in mind. Rather we have to think of a more primitive concept. In early Irish literature, our oldest source for Celtic, there are a few references to this idea, but the problem is that this literature was written at a time when Ireland was already Christianized. Apart from that, we can question the statement atque hoc maxime ad virtutem excitari putant metu mortis neglect `and they believe that this (the belief in transmigration) rouses in the highest degree virtue (in battle), neglecting fear of death. Iconographical evidence suggests that death was seen as something fearful: the Tarasque de Noves (see link) shows a monster devouring the dead with its claws on two heads with closed eyes. It could very well be that as Gaul was at war with Rome, the idea of transmigration served as a psychological incentive for Gaulish warriors not to fear death, but I am not quite convinced that this belief was as common as Caesar tells us. Besides in many so-called primitive cultures various and often conflicting ideas about the afterlife exist happily together.
 In omni Gallia eorum hominum, qui aliquo sunt numero atque honore, genera sunt duo. Nam plebes paene servorum habetur loco, quae nihil audet per se, nullo adhibetur consilio. Plerique, cum aut aere alieno aut magnitudine tributorum aut iniuria potentiorum premuntur, sese in servitutem dicant nobilibus: in hos eadem omnia sunt iura, quae dominis in servos. Sed de his duobus generibus alterum est druidum, alterum equitum. Illi rebus divinis intersunt, sacrificia publica ac privata procurant, religiones interpretantur: ad hos magnus adulescentium numerus disciplinae causa concurrit, magnoque hi sunt apud eos honore. Nam fere de omnibus controversiis publicis privatisque constituunt, et, si quod est admissum facinus, si caedes facta, si de hereditate, de finibus controversia est, idem decernunt, praemia poenasque constituunt; si qui aut privatus aut populus eorum decreto non stetit, sacrificiis interdicunt. Haec poena apud eos est gravissima. Quibus ita est interdictum, hi numero impiorum ac sceleratorum habentur, his omnes decedunt, aditum sermonemque defugiunt, ne quid ex contagione incommodi accipiant, neque his petentibus ius redditur neque honos ullus communicatur. His autem omnibus druidibus praeest unus, qui summam inter eos habet auctoritatem. Hoc mortuo aut si qui ex reliquis excellit dignitate succedit, aut, si sunt plures pares, suffragio druidum, nonnumquam etiam armis de principatu contendunt. Hi certo anni tempore in finibus Carnutum, quae regio totius Galliae media habetur, considunt in loco consecrato. Huc omnes undique, qui controversias habent, conveniunt eorumque decretis iudiciisque parent. Disciplina in Britannia reperta atque inde in Galliam translata esse existimatur, et nunc, qui diligentius eam rem cognoscere volunt, plerumque illo discendi causa proficiscuntur.
qui aliquo sunt numero atque honore: who are of a certain rank and position (numero and honore are ablatives of description)
plebes = plebs (f)
servorum habetur loco: litt: are held in place of slaves = are considered as slaves
(quae) nullo adhibetur consilio, who are not summoned to any counsil
aes alienum: someone else’s money = debt
se dico (dicare!): to give one self over to
in hos: for them, regarding them
disciplinae causa: for learning this knowledge
admitto facinus: to commit a crime (facinus facinoris (n.)
caedes –is (f.): murder
aut privatus aut populus: in private or in public
eorum decreto non stetit: does not keep standing to their decision (the perfect stetit is used for a continuous action). As also the next sentence implies – being forbidden to attend sacrifices – such people were considered as social outcasts. In traditional societies – and even today in some groups in the Western world – the emphasis falls not on the individual, but on the group as a whole and the transgression of a rule by one individual is a danger for society as a whole.
numero… habentur: are counted under the number of
aditus –us (m.): approach, contact
defugio: to avoid, shun
quid incommodi: something of misfortune
de principatu contendunt: they battle about the chief place
Carnutes: they lived near Chartres or Orleans
reperio rep(p)eri repertum: to find
illo: to Britania
 Druides a bello abesse consuerunt neque tributa una cum reliquis pendunt; militiae vacationem omniumque rerum habent immunitatem. Tantis excitati praemiis et sua sponte multi in disciplinam conveniunt et a parentibus propinquisque mittuntur. Magnum ibi numerum versuum ediscere dicuntur. Itaque annos nonnulli vicenos in disciplina permanent. Neque fas esse existimant ea litteris mandare, cum in reliquis fere rebus, publicis privatisque rationibus Graecis litteris utantur. Id mihi duabus de causis instituisse videntur, quod neque in vulgum disciplinam efferri velint neque eos, qui discunt, litteris confisos minus memoriae studere: quod fere plerisque accidit, ut praesidio litterarum diligentiam in perdiscendo ac memoriam remittant. In primis hoc volunt persuadere, non interire animas, sed ab aliis post mortem transire ad alios, atque hoc maxime ad virtutem excitari putant metu mortis neglecto. Multa praeterea de sideribus atque eorum motu, de mundi ac terrarum magnitudine, de rerum natura, de deorum immortalium vi ac potestate disputant et iuventuti tradunt.
neque tributa una cum reliquis pendunt: they don’t pay tribute together with the others
sua sponte: of their own accord
Magnum ibi numerum versuum: up to a few generations ago, it was not unusual for Brahmin sons to learn the Rig Veda by heart: more than a 1000 hymns! We have no clue how large the body of knowledge must have been, but probably considerable, as the next sentence make clear: some stayed there for 20 years to gain knowledge.
edisco edidici: learn by heart
Graecis litteris utantur: the Riviera was colonized by the Greeks from the 6th century BC, but it is questionable whether writing was much in use.
Id mihi duabus de causis instituisse videntur: they seem me to have instituted this for two reasons (This the only sentence in the whole De Bello Gallico in which Caesar is using the form mihi, as he normally writes about himself in the third person. Which reminds me of Gorbachev, who also spoke about himself in the third person.)
quod neque in vulgum disciplinam efferri velint: and because they don’t want to be spread amongst the common people
litteris confisos: trusting on writing
praesidium: help, assistance
diligentiam in perdiscendo: diligence in learning thoroughly
demitto dimisi demissum: to decrease, relax
in primis: first of all
Multa praeterea de sideribus atque eorum motu: in 1897 a calendar was found at Coligny, dating from the end of the 2nd century AD, corroborating Caesars statement about the importance of the knowledge of the movement of the stars (see link).
C. Julius Caesar. Caesar's Gallic War. Translator. W. A. McDevitte. Translator. W. S. Bohn. 1st Edition. New York. Harper & Brothers. 1869. Harper's New Classical Library.
Throughout all Gaul there are two orders of those men who are of any rank and dignity: for the commonality is held almost in the condition of slaves, and dares to undertake nothing of itself, and is admitted to no deliberation. The greater part, when they are pressed either by debt, or the large amount of their tributes, or the oppression of the more powerful, give themselves up in vassalage to the nobles, who possess over them the same rights without exception as masters over their slaves. But of these two orders, one is that of the Druids, the other that of the knights. The former are engaged in things sacred, conduct the public and the private sacrifices, and interpret all matters of religion. To these a large number of the young men resort for the purpose of instruction, and they [the Druids] are in great honor among them. For they determine respecting almost all controversies, public and private; and if any crime has been perpetrated, if murder has been committed, if there be any dispute about an inheritance, if any about boundaries, these same persons decide it; they decree rewards and punishments; if any one, either in a private or public capacity, has not submitted to their decision, they interdict him from the sacrifices. This among them is the most heavy punishment. Those who have been thus interdicted are esteemed in the number of the impious and the criminal: all shun them, and avoid their society and conversation, lest they receive some evil from their contact; nor is justice administered to them when seeking it, nor is any dignity bestowed on them. Over all these Druids one presides, who possesses supreme authority among them. Upon his death, if any individual among the rest is pre-eminent in dignity, he succeeds; but, if there are many equal, the election is made by the suffrages of the Druids; sometimes they even contend for the presidency with arms. These assemble at a fixed period of the year in a consecrated place in the territories of the Carnutes, which is reckoned the central region of the whole of Gaul. Hither all, who have disputes, assemble from every part, and submit to their decrees and determinations. This institution is supposed to have been devised in Britain, and to have been brought over from it into Gaul; and now those who desire to gain a more accurate knowledge of that system generally proceed thither for the purpose of studying it.
The Druids do not go to war, nor pay tribute together with the rest; they have an exemption from military service and a dispensation in all matters. Induced by such great advantages, many embrace this profession of their own accord, and [many] are sent to it by their parents and relations. They are said there to learn by heart a great number of verses; accordingly some remain in the course of training twenty years. Nor do they regard it lawful to commit these to writing, though in almost all other matters, in their public and private transactions, they use Greek characters. That practice they seem to me to have adopted for two reasons; because they neither desire their doctrines to be divulged among the mass of the people, nor those who learn, to devote themselves the less to the efforts of memory, relying on writing; since it generally occurs to most men, that, in their dependence on writing, they relax their diligence in learning thoroughly, and their employment of the memory. They wish to inculcate this as one of their leading tenets, that souls do not become extinct, but pass after death from one body to another, and they think that men by this tenet are in a great degree excited to valor, the fear of death being disregarded. They likewise discuss and impart to the youth many things respecting the stars and their motion, respecting the extent of the world and of our earth, respecting the nature of things, respecting the power and the majesty of the immortal gods.