Probable.

While Christmas Eve is the night par excellence of the supernatural, the whole season of the Twelve Days is charged with it. It is hard to see whence Shakespeare could have got the idea which he puts into the mouth of Marcellus in “Hamlet”:—

Some say that ever ‘gainst that season comes

Wherein our Saviour's birth is celebrated,

The bird of dawning singeth all night long;

And then, they say, no spirit dare stir abroad;

The nights are wholesome; then no planets strike,

No fairy takes, nor witch hath power to charm,

So hallow'd and so gracious is the time.

Against this is the fact that in folk-lore Christmas is a quite peculiarly uncanny time. Not unnatural is it that at this midwinter season of darkness, howling winds, and raging storms, men should have thought to see and hear the mysterious shapes and voices of dread beings whom the living shun.

Throughout the Teutonic world one finds the belief in a “raging host” or “wild hunt” or spirits, rushing howling through the air on stormy nights. In North Devon its name is “Yeth (heathen) hounds”; elsewhere in the west of England it is called the “Wish hounds.” It is the train of the unhappy souls of those who died unbaptized, or by violent hands, or under a curse, and often Woden is their leader. At least since the seventeenth century this “raging host” (das wüthende Heer) has been particularly associated with Christmas in German folk-lore, and in Iceland it goes by the name of the “Yule host.”

In Guernsey the powers of darkness are supposed to be more than usually active between St. Thomas's Day and New Year's Eve, and it is dangerous to be out after nightfall. People are led astray then by Will o’ the Wisp, or are preceded or followed by large black dogs, or find their path beset by white rabbits that go hopping along just under their feet.

In England there are signs that supernatural visitors were formerly looked for during the Twelve Days. First there was a custom of cleansing the house and its implements with peculiar care. In Shropshire, for instance, “the pewter and brazen vessels had to be made so bright that the maids could see to put their caps on in them—otherwise the fairies would pinch them, but if all was perfect, the worker would find a coin in her shoe.” Again in Shropshire special care was taken to put away any suds or “back-lee” for washing purposes, and no spinning might be done during the Twelve Days. It was said elsewhere that if any flax were left on the distaff, the Devil would come and cut it.

The prohibition of spinning may be due to the Church's hallowing of the season and the idea that all work then was wrong. This churchly hallowing may lie also at the root of the Danish tradition that from Christmas till New Year's Day nothing that runs round should be set in motion, and of the German idea that no thrashing must be done during the Twelve Days, or all the corn within hearing will spoil. The expectation of uncanny visitors in the English traditions calls, however, for special attention; it is perhaps because of their coming that the house must be left spotlessly clean and with as little as possible about on which they can work mischief. Though I know of no distinct English belief in the return of the family dead at Christmas, it may be that the fairies expected in Shropshire were originally ancestral ghosts. Such a derivation of the elves and brownies that haunt the hearth is very probable.

Clement A. Miles, from Christmas In Ritual and Tradition, Christian and Pagan