The legendary kings of Denmark are the predecessors of Gorm the Old, half history and half legend. The accounts of the Danish kings are confusing and contradictory, and so this presentation tries to separate the various sources from each other. They sometimes mention the same kings.
Harthacnut (da: Hardeknud) the father of Gorm the Old according to multiple sources, the main question is whether he was king of Denmark or only king of some part of Denmark. His parentage is also disputed, as either from an unknown king Sweyn, or from either Sigurd Snake-in-the-Eye or king Erik, both said to be children of Ragnar Lodbrok.
Sigtrygg king in the early 10th century, and either deposed by Harthacnut or contemporary depending on sources. Likely had base in Schleswig, but the extent of his realm is unknown. Son of Gnupa.
Gnupa father of Sigtrydd, according to one source shared the power with his brother Gyrd. According to Gesta Danorum, he was defeated as one of the minor border kingdoms by Gorm when he united Denmark, though that conflicts with Gnupa's son being deposed by Gorm's father according to other sources.
Sigurd Snake-in-the-Eye (da: Sigurd Orm-i-øje or Snogeøje). Mentioned by Chronicon Roskildense and Ragnarssona þáttr. Said to be king of Zealand and Scania, and son of Ragnar Lodbrok.
Ragnar Lodbrok was a legendary king probably in the 9th century, is mentioned in multiple sources, but the sources are wildly inconsistent.
Horik I said to have been the sole king of Denmark in the middle of the 9th century, and son of Sigfred.
Harald Klak King in Jutland in the beginning of the 9th century.
Gudfred (da: Godfred or Gøtrik) a Danish king in the beginning of the 9th century. Said to be father of Ogier the Dane (da: Holger Danske), and son of Sigfred.
Sigfred Danish king the end of the 8th century. Reported to have assisted the Saxons against Charlemagne.
List of legendary kings of Denmark Wikipedia
Early kings of the Rig and Scylding lines, mentioned by multiple sourcesDan mikilláti, son of Danp - (He is brother-in-law of Domar.)
Fróði mikilláti, son of Dan Mikillati
Halfdan, son of Fróði
Hroðgar (Roar), 6th century?, son of Halfdan
Halga (Helge), 6th century?, son of Halfdan
Hrólfr Kraki, son of Helga
After Hrólf Kraki no two sources give the same succession.
Adam of Bremen mentions several kings from the 10th century preceding Gorm the Old. He claims Svend Estridson as his source. Many of these are also confirmed by other sources.Helgi
Olof the Brash (Olav/Ole den Frøkne): mention o. 925
Gyrd and Gnupa: mention 934
Sigtrygg Gnupasson (Sigerich): c. 935, but conflicts with Harthacnut's deposition of him about 917
Harthacnut Very likely preceded Gorm the Old
The kings from Saxo Grammaticus' chronicle Gesta Danorum ("Deeds of the Danes").Dan I
Høtherus (and Balderus)
Rørikus (the grandfather of Hamlet)
Haraldus Hyldetan (Harald Wartooth)
The kings from the Chronicle of Lejre.Dan, son of Ypper (a primeval king of Sweden)
(Hadding) (only referred to)
Ro (= Haldan)
Haldanus (= Ro) in Lejre and sea-king Helghe, the sons of Ro (= Haldan)
A dog king Raki, Rachus or Saurr ruled Denmark on the order of the Swedish king Adils (or Hakon)
Snyo, son of Frosti
Haki or Aki, brother of Haghbardus and son of Hamundus
Frotha Largus (the Generous)
Hetha or Wysna, queen in Hedeby
Other manuscript have a supplementary list, following the name of Hartwar:Wig
Hother of Saxland, son of Hodbrod and Hadding's daughter, as nearest heir.
Rorik Slengeborre or Rake
Offe the Strong
The kings in epic poem BeowulfHeremod, a Danish king
Scyld, a foundling who became king
Scealdwea (Scealdea), son of Heremod
Beowa, son of Scyld
Healfdene, son of Beowa
Heorogar, son of Healfdene
Hroðgar, son of Healfdene
Hroðulf, probably the son of Hroðgar's brother Halga
The kings in the poem GróttasöngrSkjöldr
The kings of the saga of the Scylding family.Scioldus
Helgo and Roas
Sögubrot or Sǫgubrot af nokkrum fornkonungum Dana ok svíaveldi is an Old Icelandic saga fragment which is believed to be a part of the original Skjöldunga saga. The fragment begins in the middle of a discussion between the Scanian king Ivar Vidfamne and his daughter Auðr.Kings of the whole of Denmark or individual Danish regions, which appear in Sögubrot
Helgi, (joint ?) king of Zealand
Hrœrekr Ringslinger (brother of Helgi), king / (co-kingship) of Zealand
Ivar Vidfamne (the father-in-law of Hrœrekr), King of Scania - later King of Denmark, Sweden, Norway and parts of several adjoining countries.
Harald Wartooth (grandson of Ivar), he became king after Ivar (possibly identical with the "former" or "senior" King Harald mentioned in connection with the royal Danish brothers Anulo and Harald in the Royal Frankish Annals)
Hring or Sigurd Hring (nephew of Harald Wartooth), at first king of Sveariket (Beowulf: Swēorice; oldest Swedish form: Swerike), later also king of Denmark (could possibly be identical with king Sigfred).
At the end of Sögubrot is mentioned Ragnar (Ragnarr) as a son of Sigurd Hring. From other known sources it must be concluded that this Ragnarr is the famous Viking king Ragnar Lodbrok.
The kings of the saga of the Ynglinga family.Skjöldr
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