Kjarvalr "Írakonungr" appears in the "Landnámabók" and has been identified as Cerball mac Dúnlainge, King of Osraige who died in 888. There is clearly a chronological problem with Earl Hlodvir, whose son Sigurd was killed at Clontarf in 1014, marrying the daughter of a king who died more than 120 years before that. Furthermore, Thorstein "the Red" Olafsson (fl. late 9th century and Hlodvir's great grandfather) was apparently married to a granddaughter of Kjarvalr. Woolf (2007) concludes that the saga writers may have confused this story about the provenance of Sigurd Hlodvirsson with one about Thorstein, a close ally of Sigurd Eysteinsson.