Steinvör "the Stout" Frakokksdóttir

Olvir Rosta (Old Norse: Ölvir Rósta, and Ölvir Þorljótsson), also known as Aulver Rosta, is a character within the mediaeval Orkneyinga saga, who is purported to have lived during the early 12th century. His Old Norse byname, rósta, means "brawl", "riot". His name, and byname, appear variously in English secondary sources.

Ölvir appears in the saga as the son of Þorljót, and Steinnvör 'the Stout'. The mother of Steinnvör is Frakökk, who has been described as one of the great villains of the entire saga. One of Frakökk's sisters, Helga, is the concubine of Earl Hákon Pálsson. Part of the saga relates of how the Earldom of Orkney is for a time jointly run by half-brothers—Haraldr Hákonsson and Páll Hákonsson, who are both sons of Earl Hákon. With the death of Earl Haraldr, son of Helga, Frakökk's family falls out of favour, and are forced to leave Orkney. In time, Frakökk conspire with the father of Earl Rögnvaldr, and agrees to a plan to take the Orkney by force and split it with Earl Rögnvaldr. She and Ölvir eventually make their way to the Suðreyjar, and may their return in a bid to win half of the earldom. However, their small fleet of ships are defeated in battle against Earl Páll. The saga also tells of how Ölvir kills an Orkney chieftain who fought against him during the sea-battle—by burning the man to death within his house. The chieftain's vengeful son later tracks down Ölvir and Frakökk, at their own home in Sutherland. After a short battle behind their homestead, Ölvir's men are routed and Frakökk is burned to death within her house; Ölvir flees from the scene, making for the Suðreyjar, and is not heard from again.

Ölvir has also been associated with several places in Sutherland, some of which may bear his name. It has been proposed that Ölvir Rosta may be an ancestor of either one of two Scottish clans from the Outer Hebridean island of Lewis. In 1962 a runestone was uncovered in the Inner Hebrides which bore the name Ölvir. It has been suggested that the men mentioned on this stone were family relations of Ölvir.