Ancient Celtic Religion by Jhenah Telyndru
This is Part III of a Four-part series.
The Sacred Year
As pastoralists and agriculturalists, the lives of the Celts were intertwined with the changing of the seasons. In Britain, Iron Age Celts dwelt in small farmsteads with extended families and clan groups living together in nucleated hamlets with their privately owned land adjacent to the homestead. Because of this relative isolation, Celtic life evolved to include festival gatherings in tribal central places held for the purpose of social, cultural and economic exchange.  The religious elements of these festivals were of prime importance and reflected the agricultural and seasonal cycles, while being supplemented by the more mundane activities of trading, matchmaking, and marketing, thereby creating a medium through which the socio-economic needs resulting from the disparate settlement pattern could be met.
The Celtic year was divided into two halves — winter was the dark half of the year, and summer was the light half of the Year; as Caesar notes that the Celtic day began at sun set, and it is likewise believed that the Celtic year begins in the darkness at the onset of winter. These seasons were further halved, yielding a quaternary festival calendar which appears to be known throughout the Celtic lands, and some of whose traditions have survived into the present day. Whatever local and personal religious celebrations may have also occurred, the great gatherings accompanying each of these four festivals played an important role in Celtic socio-economic and religious life. This four-fold festival system is best known from its survival in Irish tradition,
November 1st, the Festival known Samhain (“Summer’s End”), was the start of the Celtic year. This day marked the beginning of winter as the last of the harvest was collected and the livestock were gathered into winter barracks and stockades after the excess had been slaughtered and smoked for the winter’s stores. The feast of Samhain was considered to be a liminal period, that is it was neither a part of the old year nor a part of the new, making it a day of important religious significance, and potentially fraught with danger. It was believed that at this threshold time the gods and ancestors could pass easily between the worlds and walk among the living; therefore, the Celts performed rites and ceremonies, left offerings for the dead, and performed divinations for the coming year and recounted the tales of their gods and great heroes.
The next great religious festival was Imbolc, which occurred on February 1 and was the midpoint of the dark half of the year. Imbolc, believed to mean “purification”, was considered a herald of the springtime season; ewes began to lactate, following the birth of their lambs, supplying protein from milk, cheese, and whey, which was most welcome at this time of the winter. Imbolc was sacred to the goddess Brigid – an almost pan-Celtic goddess of triple aspect, overseeing healing, metal work, and poetry. Irish tradition speaks of an eternal flame tended by 19 priestesses at a shrine to Brigid at Kildare, and she is believed to be the goddess Caesar referred to as Minerva in his account – a goddess so beloved, that she transitioned into a saint with the coming of Christianity.
Beltane was celebrated on May 1st and marked the beginning of the light half of the year, when the summer began and the world was green and growing. Good weather and the good health of animals and humans alike were anticipated and the flocks and herds were put out to pasture. Communal ceremonies included driving cattle between two fires to bless, protect, and purify them from disease-causing vermin left over from their long winter confinement. Beltane was a celebration of the fertility of land, animals, and humans alike, and was one the greatest feast days. Like Samhain, its opposite on the wheel of the year, Beltane was a transitional period between the seasons and therefore was considered to be outside of time. Thus filled with potential dangers, Beltane required rituals and sacrifices to ensure the health of the burgeoning new growth and yield an abundant growing season. 
On August 1, the festival of Lughnasadh (Gwyl Awst) was celebrated as the first day of autumn and the beginning of the harvest. It was a time for thanksgiving for the bounty of the earth and for the performance of sacrifices to ensure continued bounty for the rest of the year. The crops were welcomed and large communal meals were of great ritual importance. Lughnasadh was a festival known for its large, communal sporting events, especially horse racing, which served to reinforce the bonds between tribe members. These events – which lasted for two weeks before and after the holy day itself — were the said to commemorate the funeral games of Tailtiu, foster-mother of the Irish god Lugh, for whom the feast was named.
 B. Cunliffe, Iron Age Communities in Britain (Great Britain: Routledge and Kegan Paul, Ltd., 1975), p. 303
 Caesar, The Gallic Wars, VI, XVIII
 A. Ross, “Ritual and the Druids” in M. Green, ed., The Celtic World (London: Routledge, 1995), p. 434
 Ibid., 437
 M. Green, The Gods of the Celts, p. 72
 P. MacCana, Celtic Mythology, p. 127
 A. Ross “Ritual and the Druids”, p. 434
 Ibid., p. 436
 M. Green, The World of the Druids, p. 35
 A. Ross, Everyday Life of the Pagan Celts, p. 153
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Siculus, Diodorus, The Library of History, Loeb Classical Library, Translated by C.H. Oldfather (Boston: Harvard University Press, 1967). Available at http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Diodorus_Siculus/ home.html <Accessed 3 January 2011>
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