Óláfs saga helga
Óláfs saga helga or the Saga of St. Olaf, written in several versions, is one of kings' sagas (konunga sǫgur) on the subject of King Olaf Haraldsson the Saint.
The saga draws from skaldic poetry and Latin hagiography, with embellishments from popular oral legends.
The earliest version, the so-called Oldest Saga of St. Olaf probably written in Iceland, has not survived except in a few fragments. The next version, commonly known as the Legendary Saga of St. Olaf (also designated Helgisagan um Ólaf digra Haraldsson "Holy saga of Olaf Haraldsson the Stout" ), is preserved in a unique Norwegian manuscript, De Gardie 8 (in the possession of Uppsala University Library). A third, by Icelandic cleric Styrmir Kárason, is also now lost except as chapters excerpted and added to the Flateyjarbók recension, these fragments demonstrating evidence of a richer rhetorical style.
Snorri Sturluson not long thereafter compiled his version of the saga, written under an "overall plan" of a more secular design, in the style of "Icelandic saga tradition as well as .. secular biographies in the Latin tradition". This work has been termed the Separate Saga of St. Olaf, to distinguish it from the form that Snorri incorporated into his compendium, the Heimskringla.
Snorri may have derived his versions from the Legendary sagas and Styrmir's version, or at least, he seems to use have used the same common sources as these earlier versions.
Later redactions contain Snorri's version at the core, but are expanded using additional material. For example, the Flateyjarbók redaction (and the AM 61 variant which serves as the base text for the saga in the Fornmanna sögur series) contains a much more detailed account of the capture of the sword Bæsingr from the burial mound of Olaf Geirstad-Alf to be given to the infant St. Olaf, who is hinted as being a reincarnation of his namesake, and the subsequent use by him to combat the margýgr (mermaid, sea-hag, sea-giantess) and great boar that the heathens worship in idolatry.
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