Context:

Referenced multiple times throughout as the primary source for the Battle of Stamford Bridge narrative. Described as 'the saga of King Harold' and 'the definitive, in fact, pretty much the only account we have of the Battle of Stamford Bridge.'

Context:

Referenced as a primary source for Harold Hardrada's life, described as 'part of the cycle called Heimskringler' written about 200 years after the events. Multiple passages are quoted from this saga throughout the episode.

Context:

Described as a 13th century handbook for poets written by Snorri Sturluson, explaining that it was needed because Christian poets had forgotten the old Norse mythology necessary for traditional poetry.