"In the old Icelandic calendar, there is no indication that a year was counted as beginning on any particular day, but the First Day of Summer (sumardagurinn fyrsti) seems the logical equivalent.
In the 12th century it seems that Ari Ţorgilsson the Wise regarded September 1 as the beginning of the year, following the example of Pope Gregory VII. By the almanac of the Icelandic Church, however, the year began on Christmas Day.
By the early 16th century, January 1 seems to have been established as the beginning of the year, and the word nýársdagur (New Year's Day) first appears as a marginal note in the first printed version of the New Testament in Icelandic in 1540. Gamlárskvöld (New Year's Eve, literally Old Year's Evening), on the other hand does not appear in print until 1791 and gamlársdagur (Old Year's Day) not until 1862. Various aspects of folklore have become attached indiscriminately to Christmas Eve, New Year's Eve and even Twelfth Night. No doubt the confusion arises because New Year's Eve and Christmas Eve were for many centuries one and the same. The dead were supposed to rise from their graves, cows to receive the power of speech, and seals to take on human form, while the óskastund (wishing moment) was also supposed to occur on this night; water might also be turned into wine.
The elves, or "hidd- en people," beauti- ful beings who lived in splendid homes hidden within rocks and crags, were reputed to move house on New Year's Eve. Since the elves might call in on their travels it was regarded as necessary to sweep and thoroughly clean the house before New Year's Eve, as "the hidden people" had high standards of cleanliness. Once all was clean and tidy, the lady of the house would walk about her home, reciting a protective incantation:
Komi ţeir sem koma vilja,
veri ţeir sem vera vilja,
fari ţeir sem fara vilja,
mér og mínum ađ meinalausu.
Come all who wish to come,
Stay all who wish to stay,
Go all who wish to go,
And do me and mine no harm. "