Question: Eystein Haraldsson, was king of Norway from 1142 to 1157, "Øystein Haraldsson", is his name in which North Germanic language spoken mainly in Norway, where it is the official language?
Sentence (from "Eystein II of Norway"): Eystein Haraldsson (Old Norse: "Eysteinn Haraldsson", Norwegian: "Øystein Haraldsson"); c.1125–1157) was king of Norway from 1142 to 1157.
Relevant evidence: Yes