|The ancient Druids considered it profane to record their teachings in writing. All of their teachings were handed down by spoken word in verses or stories. People at different levels taught different categories of the ancient lore.
The highest in rank of the learned men of each Celtic people was called the Druis, or "Druid." He was advisor to his chieftain or king. The Druid had to know all the local rituals, laws, customs and myths. He also had to be skilled in the verses and songs of his people. The mythology of the Celtic tribes was preserved by people like him.
There were also female druids who specialized in cults of local goddesses. The female druid was called ueleda (we-leh-dah) or bendrui (byen-dree) in Old Irish. The ueleda or bendrui was often a priestess of a goddess such as Sulis, Brigindu or Brigantia, and lived apart from the tribe with other priestesses, guarding the goddess sacred round hearth fire.
Certain other learned men were called "seers" or "prophets" in the ancient Celtic language. These were the uelis (weh-liss), a seer and poet-magician (plural uelites); and the uatis (wah-tiss), a prophet and poet-magician (plural uates).
The term velis could almost be used synonymously with Druid, in a general sense. Indeed, after Christianity came to Ireland, velis evolved into the Old Irish fili (fee-lyih) and replaced the term Druid as a sort of secularized version, while the terms vatis and uatis evolved into the Old Irish Faith, or "prophet."
Today the modern Irish word file means "poet" and is often translated as "bard," though the rank was higher than a bard’s. It is important to understand the differences in technical terms between the old Celtic languages, because these terms are used in the old writings which preserve the oral traditions of this Celtic priesthood.
Ironically, it is because the Irish were converted to Christianity that we have authentic traditions of the Druids recorded in writing: Because the early Church used Latin as its official language, the Latin alphabet was brought to Ireland.
Ireland was the only Celtic country to convert from Druidism to Christianity. The other Celtic countries of Britain (when it was inhabited by the Welsh and Cornish, before the English came), and Gaul had been dominated by Romans who had eliminated Druidism and replaced it with Pagan Roman customs and cults in the first century. But Ireland remained a land governed by many petty Celtic kingdoms, or toutas (tribes). Even later, when the first Norse, Saxons and Normans invaded Ireland, many of them became celticized to the Gaelic language and customs, sometimes abandoning their Germanic heritage altogether. Ireland, then, remained culturally Celtic and the Church had to adapt to that.
Many of the early Irish Christian clerics had been filídh or "poets" in their native Celtic traditions before converting and becoming monks, priests, or bishops. St. Columcille was a fili before becoming a Christian. Many of these men used the Latin alphabet in their spare time to write down the Old Irish that was their native tongue, and to record their knowledge. The older religion of Druidism was often practiced side-by-side with Christianity, and scholars have noticed that while they sometimes attempted to disguise the lore, the monks also preserved very ancient Indo-European themes, customs and philosophies.
Many of these ancient and medieval Irish writings still have not been translated into English and are only available in Old or Middle Irish. It is from this literature that scholars of Indo-European comparative mythology and philology have been able to learn a great deal about the culture of the Celtic peoples.
Celts were the people of Gaul (France, Switzerland, Belgium, Bohemia and Galicia in Spain), Britain (now Wales, Cornwall and Brittany in France), Scotland and Ireland. A group of Gaulish settlers also colonized Galatia in what is now Turkey.
The Celts were closely related to the Germanic people Balts, Slavs, Romans, Oscans, Thracians, and Greeks, and were distantly related to the Aryans of Iran and India. All of these people were the descendents of tribes that inhabited Russia and the Ukraine nearly five-thousand years ago. The evidence from archaeology and linguistics demonstrates that these people had their own religions whose traditions were preserved orally down through the centuries. Celtic magic as transmitted down from the Druids to the Old Irish literature preserves much of these archaic traditions.