Tjodolf of Hvin is considered to have been the original author of Ynglingatal, a poem glorifying the Norwegian petty king Ragnvald, by describing how he was descended from the Swedish kings and the Norse gods.
With King Harold Harfagri (872-930) we get on historic ground.
To this circle of poets belong Thorbjoern Hornklofi and Thjodholf of Hvin, both authors of famous panegyrics.
Eyvind Finnsson, surnamed Skaldaspillir (spoiler of skalds), composed on King Hakon's death (961) the "Hakonarmal" on the model of the "Eiriksmal," which an unknown skald had composed in honour of the memory of King Eirikr (d.
The mare torments men at night in their sleep, at time even killing them, as happened to the Swedish king Vanland, according to Ynglingasaga, Chapter 16.
The story is told us in a strophe of the scald Thjodholf:
The origin of the whole conception may be traced to the nightmare, the distressing dream that is accompanied by the feeling of physical pressure; the "mare," usually thought of as feminine, causes a feeling of suffocation and depression, and, as incubus or succubus, is also represented as holding carnal intercourse.