Authorship: The Family Sagas ( Íslendingasøgur ) are essentially anonymous. Further, they are remarkably uniform in style. Some scholars find stylistic distinction in a group of sagas from eastern Iceland (the Austfirðingasøgur ); otherwise there are no internal features to distinguish authors or to identify a particular saga with a known author. There are a very few exceptions. Egils saga Skallagrimssonar is traditionally ascribed to Snorri Sturluson, but without any certainty, and a portion of the sprawling Sturlunga Saga was written by Snorri's nephew, Sturla Þorðarson.

Free Prose vs. Book Prose: Proponents of the "Free Prose" theory argued that the sagas developed in oral tradition and were recorded later. "Book Prose" theory held that the sagas are a literary creation. Much of the debate erroneously focused on historicity: it was assumed that oral sagas fashioned contemporaneously with events would be historically accurate, and inaccuracies were the result of later, written accounts. Oral histories were (and remain) important in the culture, but there is no evidence of an oral, saga-like tradition. Conversely, it is possible that the written sagas have influenced modern oral storytelling style to a certain extent.

Ari the Learned: Ari Þorgilsson, "the Learned" ( hinn fróði ), (1067-1148) was an important figure. A careful historian of the settlement of Iceland, his scholarly vernacular prose is distinct from the literary sagas, but his Libellus Islandorum (often called somewhat inaccurately Íslendingabók after a lost work said by Ari to contain kings' lives and genealogies in addition to the information repeated in Libellus Islandorum) was a source of information to the saga writers, who often quote him. Modern scholars also rely on Ari's work to date many of the events described in the sagas.