Association of Polytheist Traditions
WinternightsCopyright © by Stormerne and Arlea Hunt-Anschütz 2005
A sacrifice was to be made for a good season at the beginning of winter... 
In pre-Christian Scandinavia, Veturnætur, Winternights, was a period of two days around the middle of October which marked the beginning of the winter half of the year. At this time the cattle would be brought in from the pastures and, as there was only fodder enough to see the breeding stock through the cold season, the remainder would be slaughtered and the meat preserved to provide food for the farmers throughout the harsh winters. This necessary yearly cull provided an excellent excuse for a big sacrificial feast at which gods, elves and/or ancestors were welcomed. Friends, relatives and honoured guests would gather at farmstead feast halls decorated with festive tapestries. Descriptions in the Icelandic Sagas suggest that they would play ball games on the frozen lakes during the day and eat and drink to excess during the night.
A passage in the Saga of Hakon the Good  by the medieval Icelandic historian Snorri Sturlusson describes a typical heathen blót or sacrifice. The livestock were killed in a ritual manner and their holy blood was sprinkled over both idols of the gods and the people present. The meat was then cooked in kettles hung over a fire running down the centre of the hall. The chieftain hosting the feast blessed the sacrificial meat which was then shared out amongst the guests. A sacred horn or beaker of ale or mead was born around the fire and blessed by the chieftain. The guests then drank toasts to gods and ancestors.
One account of a Winternights celebration specifically mentions a blót to the god Frey.
Thorgrim decided to give an autumn feast on the eve of the winter season, and to welcome winter and make a sacrifice to Frey, and he invites his brother Bork, and Eyjolf Thordsson and many other important men. Gisli also makes ready a feast and invites his wife's kinsmen from Arnarfjord, and the two Thorkells, and no fewer than sixty men were expected at Gisli's. There was to be drinking at both houses, and the floors at Saebol were strewn with rushes from the rush-pond. 
According to Snorri:
Freyr is the most glorious of the Æsir. He is ruler of rain and sunshine and thus of the produce of the earth, and it is good to pray to him for prosperity and peace.
Perhaps some heathens made offerings to Frey at the beginning of Winter to thank him for good harvests over the past year and to ensure good harvests in the coming year.
Other accounts of Winternights make reference to the Dísir. The word Dísir simply means 'ladies' or 'maidens'. The Dísir were a family's female ancestral spirits who, according to various accounts, could behave like guardian angels, protective warrior goddesses, or fetches appearing to those about to die.
Viga-Glum's Saga tells us that:
A feast was held at the beginning of Winter, and sacrifice made to the spirits [Disir], and everyone had to take part in this observance. 
Another passage which mentions the Dísir most likely refers to Winternights, although we're only told that these events take place in the autumn.
King Eirik and Gunnhild arrived in Atloy the same night. Bard had prepared a feast for him, because sacrifice was being made to the Disir. It was a splendid feast with plenty to drink in the main room.