Not to split hairs (though this is a sharp sword...), I wish to clarify a few things about the Wild Hunt:

1. That the Wild Hunt and he who leads it are known by many names:

2. The appearance of the hunt is usually uniform: "A great noise of barking and shouting is heard; then a black rider on a black, white, or gray horse, storming through the air with his hounds, followed by a host of strange spirits, is seen. The rider is sometimes headless. Sometimes, particularly in Upper Germany, the spirits show signs of battle-wounds or death by other forms of mischance. Fire spurts from the hooves and eyes of the beasts in the procession. The horses and hounds may be two- or three-legged. Often the newly dead can be recognized in the train. The furious host is always a peril to the human being who comes into its way, though sometimes it leaves rewards as well." --Kveldulf Hagen Gundarsson, from Mountain Thunder, Issue 7, Winter 1992.

3. Time:
No surprise, it is usually at one of the pagan holidays: Halloween, Beltaine, Mother's Night, Yule.

4. The Hunt of the Souls
The Wild Hunt is led by a psychopomp--the leader of souls to the Underworld. On certain nights--holy days--one could see the Hunter come for his prey. That the myth exists in Norther European cultures and their American descendents, as opposed to the Mediterranean and Middle Eastern cultures, is not surprising, for while the North certainly had agriculture, they also survived by hunting, particularly in the winter, when most of the legends of the hunt take place.