Ynglinga saga
Sturluson's "Ynglinga saga" was created far too late to serve as a reliable source in regards to the events and kings it describes, being separated from the earliest ones by several centuries. "Ynglinga saga" appears to have been based on an earlier scaldic poem, "Ynglingatal", which is quoted at length by Snorri. "Ynglingatal" is not a reliable source either, though traditionally believed to have been composed at the end of the 9th or beginning of the 10th century, it might be from as late as the 12th century. Sturluson would have had access to older (now lost) manuscripts when writing the "Ynglinga saga", but this does not necessarily corroborate anything that appears in the "Ynglinga saga" as true. What is genuine history and what is myth and legend is today impossible to determine, and everything contained in the saga must as such be regarded as legendary, if not fictional. Modern scholarship does not see sagas such as the "Ynglinga saga" as good sources for genuine historical information. As a historical source, the "Ynglinga saga" is much better used as a source on historiography and society during Sturluson's own time than as a source on Sweden's early history.