The Festival Cycle
The primary days of the Celtic festival calendar were the cross-quarter days, so called because they fall on the quarter-marks of the cross formed by the solstices and equinoxes. The four quarters represented the four major festivals of the Celtic calendar, celebrated at the midpoints between the solstices and equinoxes of the solar cycle. These were determined by an additional lunar reckoning, coinciding with the beginning of the lunar cycle nearest the midpoint between the solstices and equinoxes.
Originally, there were likely only three festivals, each of three days' length, probably hearkening back to the ancient reckoning of time by the three-month cycles of the sun. Later, these became four, possibly when Celtic culture moved to an agricultural calendar or maybe due to the influence of the Roman calendar. The Cath Mag Tuireadh, which appears on the surface to be a collection of simple folk tales, is actually in many ways a calendrical myth. It explains that the Tuatha Dé Danann had four important dates, which correspond to the four stations of the sun:
Spring (The Equinox), for plowing and sowing
Summer (The Solstice), for the ripening of the grain
Autumn (The Equinox) for the harvesting of the grain
Winter (The Solstice), for rest and consuming the harvest
In the course of the tale, the solar deity Lugh, who also represents the technological endeavors of man, wars against the giant Balor, who represents the unharnessed sun. Lugh emerges victorious, and the spoils of the victory include the secrets of agriculture granted by the ancient agricultural deity Bres, who promises additional harvest times in order that his life be spared. Lugh agrees, and the Tuatha Dé Danann go on to become the masters of agriculture.
The imagery of the solar wheel is repeated throughout Celtic mythology. In many cases, the name of the goddess is quite literally “Wheel.”
The four cross-quarter festivals are today often called fire festivals, from the traditional sacred fires that featured at the center of the celebrations. They went by various names depending on location, but for the sake of convenience, they are most often referred to today by their Gaelic Irish names. Although they were of obvious significance, little has been recorded about the observations of the solstices and equinoxes.
These are the eight spokes of the reconstructed Celtic calendar:
Samhain, or “summer's end”: Marked a return to cooler weather and the beginning of the winter season. Samhain was the principal festival of the ancient Celts, and most likely the oldest.
Midwinter, or the winter solstice: Marked the rebirth of the sun.
Imbolc: Marked the end of the winter season and the renewal of life. Imbolc is the newest of the festivals, possibly added with the adoption of the Latin calendar systems.
Beltaine: Marked the arrival of summer and a commemoration of fertility.
Midsummer, or the summer solstice
Lughnasadh: Marked the beginning of the hotter “dog days” of summer and the peak of the agricultural season.
The Liturgical Cycle
In the early days of European Christianity, most individual churches followed their own liturgical calendars, making their own calculations for Easter and celebrating masses and feasts of their own choosing. Over time, however, most calendars began to conform to one another.
It is curious, however, to see which feasts remained important over time and how well they adhered to the ancient festival cycles. When compared to the dates of the pagan Celtic calendar, the following days stand out:
All Hallows and All Saints, celebrated at the beginning of November
Christmas, the nativity of Christ, celebrated near the winter solstice
Candlemas, or the Feast of Brighid, celebrated on February 2, the day of Imbolc
Easter, of the resurrection of Christ, celebrated near the vernal equinox
The Feast of John the Baptist, observed at the summer solstice
Transfiguration, and the “First Fruits of Redemption,” celebrated a few days after the traditional date of Lughnasadh, as well as the autumn feast of Lammas
Oddly, many of the solar dates of the Christian calendar were decided by Roman observations. While the Bible gives no particular nativity date for Christ, early Church fathers wrote that the date was chosen deliberately to correspond to “wicked” pagan feast days, to prevent new believers from being tempted by pagan revelry. Whether latter coincidental dates were chosen for similar reasons is a matter of some controversy.