Ragnfrid Halfdanson, king of Denmark

http://fmg.ac/Projects/MedLands/DENMARK.htm#Halfdandied810B

Halfdan had [six] children:

5. RAGNFRID (-killed in battle 814).

• Einhard's Annales record that news of the death of "Hemmingus Danorum rex" arrived in 812, that "Sigifridus nepos Godofredi regis et Anulo nepos Herioldi quondam regis" both claimed the succession, and that the faction supporting "Anulonis" was victorious, with "fratres eius Herioldum et Reginfredum" being installed as kings[100].
• The Annales Fuldenses record the death in 812 of "Hemmingo Danorum rege", the succession dispute between "Sigifredo nepos Godofredi regis et Anulo nepos Herioldi", the battle in which both were killed but which Anulo's supporters won, and the accession by "Herioldum et Reginfredum fratres eius regis"[101].
• Adam of Bremen names "Reginfridum et Haraldum" as successors to Anulo but does not specify their relationship to each other[102].
• Einhard's Annales record that "Harioldus et Reginfredus reges Danorum" sent envoys to Emperor Charlemagne in 812 asking for the release of "fratrum suum Hemmingum"[103].
• He and his brother were driven out of Denmark by the sons of King Godefrid in 813. He and his brother Reginfred attacked the sons of King Godefrid in 814 in an attempt to regain the throne but were defeated, Reginfred being killed[104].
• Einhard's Annales record that "Harioldus et Reginfredus reges Danorum" who, in the previous year had been expelled from Denmark by "filiis Godofredi", attacked again in 814 but "Reginfridus et unus de filiis Godofredi qui maior natu erat" were killed[105].