Háttalykill inn forni, also known in short as Háttalykill, is an Old Norse

Old Norse

Old Norse is a North Germanic language that was spoken by inhabitants of Scandinavia and inhabitants of their overseas settlements during the Viking Age, until about 1300....

 poem, attributed to Rögnvaldr Kali Kolsson of Orkney and Hallr Þórarinsson in the Orkneyinga Saga

Orkneyinga saga

The Orkneyinga saga is a historical narrative of the history of the Orkney Islands, from their capture by the Norwegian king in the ninth century onwards until about 1200...

. The poem survives only in late manuscripts. The form of the poem is mainly greppaminni, principally a form of questions and corresponding answers.

The subject matter of the poem is a listing of heroes, both legendary and historic. The style is vernacular.