The Celts accounted for only two seasons, winter and summer, and both were celebrated at their ends and at their midpoints. The remainder of the Celtic calendar was complex, figured on a lunar cycle aligned to agricultural cycles. The beginning of each season was celebrated at the end of the last, and the solar events (“gates”) that opened each season were considered particularly numinous times — fairies roamed the earth, and witches were considered to be especially active.

The notion of the seasons was regarded as a pageant of the gods, an endless cycle of seasonal battles between the god of light and his shadow self. One such pair is the Irish Lugh and Balor. The August 1 feast of Lughnasadh was not just a commemoration of Lugh but a foreshadowing of his symbolic “death,” as well as the ascendancy of the harsher solar aspect, personified by Balor, the giant whose baleful glare destroys all it alights on. The cold months see the fertile and youthful sovereignty goddesses take on the aspect of the Cailleach, the hag of winter.