The first version, known as the Prestssaga Guðmundar byskups, was composed soon after Guðmundur's death in 1237, possibly at the instigation of abbot Lambkárr Þorgilsson (d. 1249).
It recounts the bishop's life as a young man and priest but stops abruptly during a description of Guðmundr's voyage to Norway for consecration in 1202.
However, it is preserved only through its integration into the later Guðmundar sögur and Sturlunga saga.
A series of four sagas about Bishop Guðmundr, known as Guðmundar sögur A, B, C, and D, were then written between 1314 and 1344, in what seems to have been a concerted attempt to canonise Guðmundr.
Stefán Karlsson has connected the composition of Guðmundar sögur A, B, and possibly C, to the translation of Guðmundur's relics by Bishop Auðunn rauði Þorbergsson in 1314, while Guðmundar saga D was apparently composed by Arngrímr Brandsson for the second translation of Guðmundur's relics by Bishop Ormr Ásláksson in 1344.