Source 2: http://www.druidsgrove.com
The Romans recorded that the Druids sacrificed condemned criminals. Judicial executions were no different elsewhere in Europe, including Saxony. The Romans wrote that such victims were tied into huge wicker man-shaped effigies and burned alive. There were also some forms of punishment in Celtic law deemed worse than death, such as banishment. Some mythologies describe one person's life being sacrificed so that a terminally ill noble would survive, thus indicating a belief in a cosmic balance of forces. The archeological record does reveal a number of sacrificial deaths, such as "triple-deaths", of which the most famous is the "Lindow Man", who was recovered from a bog near the border of Wales on 1st August 1984. He had been simultaneously strangled, drowned, and clubbed. The absence of any signs of struggle on the body seems to indicate that he did no t resist the sacrifice but rather agreed to it willingly. To the Celts, death was not the frightening, final thing it is to most of us born in the 20th century (see Belief), and human sacrifice may not have been so immoral. Rather, it was a very special and powerful ritual, performed only in times of serious need. It is important not to assume that ancient people held the same values that we do today.
However, there is some debate over this; the written records of Druid sacrifices may have been nothing more than anti-Druid propaganda. Julius Caesar had good reason to make the Druids look bad, because, after all, he was trying to conquer them. It would fuel interest in his campaign back home if he could prove that the Celts engaged in such barbaric practices. Yet the Romans would kill people in gladiatorial games, for the entertainment of the people. The Druids, if they did sacrifice people, could claim religious sanction. The archeological record is ambiguous if such sacrifice was judicial or ceremonial. Furthermore there is no evidence of human sacrifice in Ireland's archeology, to my knowledge, though there is evidence of animal sacrifice there.
Rest assured that modern Druids do not sacrifice anything at all.
Druidic Misconceptions – Source 2
Since the early Romantic Revival of Druidism, which began in the early eighteenth century, there have been many ideas on Druidism that owe more to imagination than to history. Here are some of the most common:
"The Barddas": a book of Welsh Bardic and Druidic knowledge. This book is known to be almost entirely forged by its author, Iolo Morganwyg. It claims as a source the "Book of Pheryllt", which is also a fictional work. It makes good poetry, but very poor history. Distinguishing the two is important, but almost never easy. (see also Romantic Druidism)
The Druids were Monotheists": A popular idea during the Romantic Revival, but without historical sanction, for there were many large and complicated pantheons of Deities, and not all were common to all the Celtic nations. Many of Druidism's early revivers were strongly influenced by Freemasonry and other similar fraternal orders, and attributed to Druids the worship of an exclusively male Christian God. Also, more recently, some have believed that the Druids worshipped the Earth Mother exclusively, but while Earth-mother Goddesses are present in the Celtic pantheons, they are not usually worshipped exclusively.
"The Druids were from Atlantis": There are many myths of magical islands in the Atlantic, but Atlantis was not one of them. The earliest documented evidence on Atlantis comes from Plato, who was a Greek and not a Celt, and was probably writing an allegory and not a history. He wrote that the chief god of Atlantis was Poseidon, a Greek (not Celtic) God.
"Pumpkin Blossoms were a Holy Druidic Tree": Pumpkins are, for one thing, not trees, and secondly, not native to Europe. The ancient Druids could not have been aware of their existence. The Jack-o-Lantern used at Halloween (Samhain) would have been a turnip, but that is not a tree either. The function of the jack-o-lantern was to ward off the souls of the dead, but this tradition owes its origin to Mediaeval times, for the Celts had no great fear of death.
"Samhain was a Celtic God": Samhain is the name of a festival, not a God of the Dead, though the festival is associated with the dead. In the Mediaeval times the fear of the dead, and of the old religion, was taught to the populace in order to integrate Christianity more completely. Indeed, most of the things we typically associate with Halloween (vampires, devils, etc.) come from this period and not Celtic myth.
"The Ogham Alphabet was used by Druids for divination": Virtually all the Ogham inscriptions that exist are burial monuments, property divisions, or landmarks. The University of Cork has an excellent collection of them. It's not enough evidence to claim that Ogham was used as an oracular tool by Druids, however, many modern Druids do use Ogham effectively for that purpose. Historians cannot be certain because any Ogham inscriptions carved on wood have rotted away long ago; only stones remain. Each letter in the Ogham alphabet was also the name of a tree, which may have had a mystical meaning associated with each tree. (see also Ogham )
"The Druids were celibate": Actually Druids were encouraged to marry and raise families. The Irish seer Cathbhad was the father of Conchobar Mac Nessa, for example. (see Women) This misconception is another attempt to christianize the early Druids.