Gudbrand Vigfússon (1887) identified several different components to the saga, which may have had different authors and date from different periods. These are: Fundinn Noregr chapters 1–3 Iarla Sogur chapters 4–38 (of which the sections regarding Earl Einarr are the oldest texts in the saga as a whole) St Magnus saga chapters 39–55 Iarteina-bok (Magnus's "Miracle book") chapter 60 The History of Earl Rognwald and Swain Asleifsson chapters 56–59 and 61–118.
Gudbrand Vigfússon (1887) identified several different components to the saga which may have had different authors and date from different periods These are Fundinn Noregr chapters 1–3 Iarla Sogur chapters 4–38 (of which the sections regarding Earl Einarr are the oldest texts in the saga as a whole) St Magnus saga chapters 39–55 Iarteina-bok (Magnus's "Miracle book") chapter 60 The History of Earl Rognwald and Swain Asleifsson chapters 56–59 and 61–118