The earliest references to it are in the form of month names, where the Yuletide period lasts somewhere around two months, falling along the end of the modern calendar year between what is now mid-November and early January. Attestations Months, heiti and kennings Yule is attested early in the history of the Germanic peoples; in a Gothic language calendar of the 5–6th century it appears in the month name , and, in the 8th century, the English historian Bede wrote that the Anglo-Saxon calendar included the months or corresponding to either modern December or December and January. While the Old Norse month name is similarly attested, the Old Norse corpus also contains numerous references to an event by the Old Norse form of the name, . In chapter 55 of the Prose Edda book , different names for the gods are given; one is "Yule-beings" (). A work by the skald Eyvindr skáldaspillir that uses the term is then quoted: "again we have produced Yule-being's feast [mead of poetry], our rulers' eulogy, like a bridge of masonry". In addition, one of the numerous names of Odin is , referring to the event. Heitstrenging Both Helgakviða Hjörvarðssonar and Hervarar saga ok Heiðreks provide accounts of the custom of . In these sources, the tradition takes place on Yule-evening and consists of people placing their hands on a pig referred to as a sonargöltr before swearing solemn oaths. In the latter text, some manuscripts explicitly refer to the pig as holy, that it was devoted to Freyr and that after the oath-swearing it was sacrificed. Saga of Hákon the Good The Saga of the Good credits King Haakon I of Norway who ruled from 934 to 961 with the Christianization of Norway as well as rescheduling Yule to coincide with Christian celebrations held at the time. The saga says that when Haakon arrived in Norway he was a confirmed Christian, but since the land was still altogether heathen and the people retained their pagan practices, Haakon hid his Christianity to receive the help of the "great chieftains". In time, Haakon had a law passed establishing that Yule celebrations were to take place at the same time as the Christians celebrated Christmas, "and at that time everyone was to have ale for the celebration with a measure of grain, or else pay fines, and had to keep the holiday while the ale lasted."