Short answers, pulled from the story.
Old Norse literature refers to the vernacular writings of the Scandinavian people produced up to around 1350. Most of it consists of Icelandic writings, though it also includes texts composed in Scotland, England, and other areas of Norse settlement.
The Orkneyinga saga, also called the History of the Earls of Orkney, is a historical narrative covering the Orkney Islands from their capture by the Norwegian king in the 9th century to around 1200. It is one of the key surviving texts of Old Norse literature set in Britain.
Hofudlausn, meaning Head's Ransom, is a skaldic poem attributed to Egill Skalla-Grimsson. It was composed in praise of King Eirik Bloodaxe in the Kingdom of Northumbria, and its name reflects the tradition that Egill wrote it to save his own life.
Several Old Norse texts relate to Scotland, including the Orkneyinga saga, the Njals saga (which includes scenes set in Orkney and Wales), and fragments of Norse poetry composed in Scotland. Among the runic inscriptions at Maeshowe on Orkney, one text has been identified as irregular verse.
20th-century poet George Mackay Brown was influenced by the Orkneyinga saga, drawing on it notably for his 1973 novel Magnus. Brown worked in Orkney, the same islands the saga chronicles.
Skaldic poetry was one of the most technically demanding verse forms in the Old Norse tradition. Hofudlausn, attributed to Egill Skalla-Grimsson and composed in Northumbria, is among the best-known surviving examples of the form.