Hálfdan "Swarti" Gudrødsson King of Vestfold
- Marriage: Ranghilda Sigurdsdóttir
- Died: Abt 860
Another name for Hálfdan was Halfdan "the Black" King of Vestfold.
~Ancestral Roots of Certain American Colonists Who Came to America before 1700, 8th Edition, Halfdan "the Black" King of Vestfold, Agdir, Raumarike, and Sogn, married as his second wife, Raghild, daughter of Sigurd Hiort, King of Ringerike and Thyri, daughter of Klak-Harald, King of the Jetland. 160
Hálfdan married Ranghilda Sigurdsdóttir, daughter of Sigurd "Hjort" Helgisson King Of Ringerike and Thyri Klacksdottir.