In contrast to the few runic fragments, a considerable body of literary and historical sources survive in Old Norse manuscripts using the Latin script, all of which were created after the conversion of Scandinavia, the majority in Iceland.
Some of the poetic sources in particular, the Poetic Edda and skaldic poetry, may have been originally composed by heathens, and Hávamál contains both information on heathen mysticism In addition there is information about pagan beliefs and practices in the sagas, which include both historical sagas such as Snorri Sturluson's Heimskringla and the Landnámabók, recounting the settlement and early history of Iceland, and the so-called sagas of Icelanders concerning Icelandic individuals and groups; there are also more or less fantastical legendary sagas. Of the originally heathen works, we cannot know what changes took place either during oral transmission or as a result of their being recorded by Christians; One important written source is Snorri's Prose Edda, which incorporates a manual of Norse mythology for the use of poets in constructing kennings; it also includes numerous citations, some of them the only record of lost poems, such as Þjóðólfr of Hvinir's Haustlǫng.
The Germanic languages likely emerged in the first millennium BCE in present-day northern Germany or Denmark, after which they spread; several of the deities in Old Norse religion have parallels among other Germanic societies.
During the Viking Age, Norse people left Scandinavia and settled elsewhere throughout Northwestern Europe.
By the twelfth century Old Norse religion had succumbed to Christianity, with elements continuing into Scandinavian folklore.
Snorri's Prologue eumerises the Æsir as Trojans, deriving Æsir from Asia, and some scholars have suspected that many of the stories that we only have from him are also derived from Christian medieval culture.
and describes religious practices of several Germanic peoples, but has little coverage of Scandinavia.
The Norwegian king Hákon the Good had converted to Christianity while in England.
On returning to Norway, he kept his faith largely private but encouraged Christian priests to preach among the population; some pagans were angered and—according to Heimskringla—three churches built near Trondheim were burned down. Religious Ruler Ideology' in Pre-Christian Scandinavia: A Contextual Approach".