The date of composition of the lost written archetype of Fóstbrœðra saga has been the subject of considerable dispute.
The skaldic stanzas attributed to Þormóðr kolbrúnarskáld Bersason appear genuine (according to Guðni Jónsson in Björn K. Þorólfsson and Guðni Jónsson 1943: lxi); he would have composed ca.