[6] Halfdan svarti ‘Hálfdan svarti (“the Black”)’: King of the districts Ringerike, Romerike, Hedmark and Vestfold in south-eastern Norway and the father of Haraldr hárfagri, who is thus the erfivǫrðr ‘heir’ (l. 7) of Hálfdan and the subject of sts 4-9. See HsvHkr (ÍF 26, 84-93).