Crueltide

Crueltide is a Discworld holiday marking the half-way point through the full 800-day Discworld year, the mid-point of Spindlewinter, the first of the year’s two Winters. It is mentioned only in the footnote in The Colour of Magic which explains the Disc’s seasons, where it said to alternate with “Hog’s Watch Night”, which marks the end of the full 800-day year.

Crueltide is then never mentioned again, and in later books Hogswatch is treated as though it happens at the end of every Winter. While this has caused some confusion, the seeming contradiction was explained in The Discworld Companion.

Simply, as a 400-day cycle of one of each season has become the more commonly used definition of a “year” (thanks in part to the University Calendar, but mostly due to the practicalities of farming), in most areas folks just use the one name, Hogswatchnight, for every Winter festival. Similarly, Small Gods’ Eve is said to be the early half-year equivalent of Midsummer Eve, but again most folks just celebrate Midsummer Eve (also known as All’s Fallow) every Summer.

In older times when the full year calendar was more in favour, presumably there were distinct Crueltide traditions. But as gods and god-like beings are created and sustained by belief, and the observance of just one set of yearly traditions every 400 days became more common, no doubt the Hogfather started to visit every Winter, as those who believed in him expected. Perhaps somewhere out there is a forgotten counterpart to the Hogfather, subsisting on the scraps of belief from those who like to say “Well, actually it's only a half-year, so technically it's Crueltide” every other year...