'''バイキングの息子、トルストンのサガ''''''Þorsteins saga Víkingssonar''' or '''The Saga of Thorstein, Viking's Son''' is a [[legendary saga]] which takes place in the 7th century. It is about the father of [[Frithjof]] the Bold. は7世紀にあったとされる伝説で、「大胆なフリッチョフ(Frithjof)」の父の物語である。 It begins in [[Norway]] and [[Sweden]] (with locations such as [[Ulleråker]]), but continues into exotic places such as [[India]]. It is not one of the more famous sagas, but it is still considered to be an entertaining story. It is a prequel to ''[[Friðþjófs saga ins frœkna]]'', ''The Saga of Fridthjof the Bold''.
It has been compared to the runestone Sö 54 in Bjudby, [[Södermanland]], [[Sweden]], as it also mentions a prominent family, and it besides the father ''Víkingr'' names three sons with the same names, and there are also close correspondences with the other names.<ref>"Tales of Generations: A comparison between some Icelandic and Geatish narrative motifs", by Guðmundsdóttir, Aðalheiður. (2016) - In: Scripta Islandica vol. 67 (2016) p. 5-36</ref>
Thorsten and his son [[Frithiof's Saga|Frithiof]] inherit the magic sword Angurvadel and the magic ship ''Ellida'' from Viking. Descendants of Thorstein appear in ''[[Friðþjófs saga ins frœkna]]'', and in the Starkad section of ''[[Gautreks saga]]''.