List of legendary kings of Denmark

The legendary kings of Denmark were, according to legend, the monarchs of Denmark, the Danes, or specific lands of Denmark (Zealand, Jutland or Scania) who preceded Gorm the Old, a king who reigned c. 930s to c. 960s and is the earliest reliably attested Danish ruler. Gorm's son, Harald Bluetooth, oversaw the widespread Christianization of Denmark, meaning that the legendary kings listed here are those from before Christianization and are predominantly (but not entirely) pagan. Earlier kings may be partly historical (especially those near to Gorm's time), but are either semi-legendary or entirely mythological. Some are based on earlier euhemerised stories (that is, figures from mythological folktales were depicted as historical kings by medieval writers such as Saxo Grammaticus).

There are many medieval accounts of the Danish kings of the Dark Ages, and these accounts can be confusing and contradictory (although there is overlap and different sources can include the same kings). This article presents the legendary kings from each source separately.

Adam of Bremen

Adam of Bremen was an 11th century German chronicler. Although not Danish himself, he spent time in the court of the Danish king Svend Estridson. Adam claims to derive much of the information on Danish history from his Latin chronicle Gesta Hammaburgensis ecclesiae pontificum ("Deeds of the Bishops of Hamburg") from conversations with Svend (whom he quotes verbatim in several places) and from information provided by Danish bishops. He also references the historians of the Franks (see, for example, the section on the Royal Frankish Annals, below) and hagiographies such as Vita Ansgarii.

Gesta Hammaburgensis ecclesiae pontificum names several 10th century kings preceding Gorm the Old. Kings whose histories are derived from information provided by Svend Estridson include:^[1]^[2]^[3]

Helge ("Heiligonem"), who ruled Norway after the defeat of the Norsemen and was renowned for his justice and sanctity (1.XLVIII)
Olaf ("Olaph"), a Swedish prince who conquered Denmark, succeeded Helge, and had many sons (1.XLVIII, 1.LII)
Chnuba and Gyrd ("Chnob et Gurd"), Olaf's sons who possessed the realm after his death (1.XLVIII)
Sigeric ("Sigerich"), who succeeded after Olaf and his sons (1.LII)
Harthacnut ("Hardegon", "Hardecnudth"), the son of "Svein"; Harthacnut came from "Nortmannia" and deprived Sigeric of the kingdom (1.LII, 1.LV)

Mentioned kings preceding Gorm the Old, whose histories are derived from other sources, include:^[4]

Gotafrid (1.xiv, 1.xxxix)
Hemming, Gotafrid's cousin who succeeded him (1.xiv)
Sigefrid and Anulo, Gotafrid's nephews who went to war with each other over Hemming's succession. Both kings were killed, but Anulo's faction won and placed Reginfrid and Harald on the throne. (1.xv, 1.xxxix)
Reginfrid, who was forced out of Denmark by his brother Harald and resorted to piracy (1.xv)
Harald (i.e. Harald Klak), who was forced out by the sons of Gotafrid and fled to the court of Louis the Pious, where he (with his wife and brother Horuch) were converted to Christianity and baptised (1.xv)
Horic, who was friedly to Christians, and who was killed in a war against his nephew Gudorm (1.xxv, 1.xxvi, 1.xxviii)
Horic the younger, the only royal survivor of the war between Horic the elder and Gudorm. On his ascension to the throne, he immediately expelled all Christian priests and closed the churches, but was later converted to Christianity by Ansgar. (1.xxviii, 1.xxix)
Sigefrid and his brother Halfdan (1.xxxvii)
Horic (1.xxxvii)
Orwig (1.xxxvii)
Gotafrid (1.xxxvii)
Rudolf (1.xxxvii)
Ingvar, son of Lodbrok (possibly a conflation of Ivar the Boneless, one of Ragnar Lodbrok's sons who is not traditionally credited with ruling Denmark, with Sigurd Snake-in-the-Eye, who is) (1.xxxvii)
Wrm (i.e. Gorm the Old, rendered in various manuscripts as "Vurm", "Wrm", "Worm", "Gorm", or "Gwyrm"), son of Harthacnut; described by Adam of Bremen as a "wyrm" who tried to eradicate Christianity in Denmark, but was succeeded by his son Harold who converted the country to that religion (1.LV, 1.LVII, 1.LVIIII, 1.LIX)

Chronicon Lethrense

More information The family tree of legendary Kings of the Danes, according to Chronicon Lethrense ...

The family tree of legendary Kings of the Danes, according to Chronicon Lethrense

Kings of the Danes are in bold and marked with an asterisk (*).

♂ Ypper, King of Uppsala

KEY

♂ Nori

♂ Østen

♂ Dan*

♀ Dannia

Marriage or coupling

Parent and child

♂ Rolfcarl, aka Rolf, a baron

♂ Ro*

♀ Ro's wife

Succession by other means

♀ Thora

♂ Helge*

♂ Halfdan*

♂ Athisl, King of Swethia

♀ Ursula

♂ Raka*, a dog

♂ Siward Albus

♂ Snyo*

♂ Hiarwart†*

♀ Sculd

♂ Rolf*† Kraki

♂ Hamund

♂ Aki*

♂ Haghbard

♀ daughter of Rolf Kraki

♂ Fritleff*

♂ Frothi* Largus

♂ Ingyald*

♂ Olav*

♀ Asa*

♂ Harald* Hildetan (war-tooth)

♀ Hethae*

The source used for the genealogical information and name spellings is the English translation provided by Mischa Hooker of Augustana College.

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The earliest known chronicle of Danish kings to be written in Denmark was Chronicon Lethrense ("The Chronicle of Lejre"), which was composed by an unknown author, likely from Roskilde and transmitted as part of the Annales Lundenses (although it was likely originally a separate work). Chronicon Lethrense was written in the mid- to late-12th century, possibly alongside or as a sort of prequel to Chronicon Roskildense, which depicts historical kings after the Christianization of Denmark.

Chronicon Lethrense was hugely influential, and many subsequent chronicles were at least partly based on it. Almost all monarchs mentioned appear in subsequent chronicles, with the notable exception of two queens regnant, Asa and Hethae. It states that the first king of the Danes was a certain Dan (after whom the tribe was named), who was the son of a Swedish king named Ypper. This is said to be both when Augustus invaded Denmark and during the time of the Biblical King David, referring to two rulers who lived about a thousand years apart.

Chronicon Lethrense also explicitly conflates the kingdoms of Denmark with Dacia, a conceit that appears in the earlier works of Dudo of Saint-Quentin, and in subsequent works such as Historia Regum Britanniae (see below).

Monarchs in the Chronicon Lethrense are:^[5]

Dan, son of Ypper (a primeval king of Sweden)
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
Rolf Kraki
Hiarwart
Aki, brother of Haghbardus and son of Hamundus
Fritleff
Frotha Largus (the Generous)
Ingyald
Olavus, who is described here as the son of Ingyald and not a conqueror as in other chronicles
Asa, queen
Haraldus Hyldetan
Hethae, queen who founded Hethaeby in Jutland

Sven Aggesen

The family tree of legendary Kings of the Danes, according to Brevis historia regum Dacie by Sven Aggesen

Kings of the Danes are in bold.

Skiold

KEY

Frothi

Halfdan

Marriage or coupling

Parent and child

Helghi

Inheritance by other or unclear means

Rolf Kraki

Rokil Slagenback

Frothi the Bold

Wermund

Uffi

Dan the High-minded,
or the Proud

Frothi the Old

Frithlefer

Frothi Frithgothæ,
or the Magnificent

Ingiald

Olaf

Regner Lothbrogh

daughter

Sighwarth

Knut (first of that name
in Denmark)

Snio

Klak-Harald

Gorm Løghæ

Thyrwi, the Ornament
of the Realm

historical kings of Denmark

The source used for the genealogical information and name spellings is the English translation by Eric Christiansen.

Sven Aggesen was a 12th century Danish chronicler who wrote Brevis historia regum Dacie ("A Short History of the Kings of Denmark"). He was a contemporary of Saxo Grammaticus and noted in his writings that he was aware of Saxo's then-in progress work on the Gesta Danorum (see below), but also described himself (incorrectly) as the first writer to document the kings of Denmark.

Sven says that the first king of Denmark was Skiold, whose descendants are the Skioldungar. The line of kings continues from Skiold to Gorm the Old with only one break, between Ingiald and Olaf. It says, "After his [Ingeld's] time no son succeeded his father to the throne for a space of many centuries. It passed to grandsons, or nephews, who, to be sure, were sprung from the royal stock on the one side." It is unclear if this represents a gap in the lineage (i.e. that other unmentioned kings ruled between Ingeld and Olaf) or if Olaf succeeded Ingeld directly but began a period in which there was no direct father-to-son succession. The latter is possible given, for example, that Olaf took the throne by conquest, and that after Olaf the landowner Ennignup (possibly a reference to Gnupa) became guardian of the kingdom before Knut came to power. When first written, the chronicle was apparently accompanied by an extensive genealogy as an appendix, but this appendix has not survived.

Gesta Danorum

More information The family tree of legendary Kings of the Danes, according to the Gesta Danorum (Books I to VII) ...

The family tree of legendary Kings of the Danes, according to the Gesta Danorum (Books I to VII)

Kings of the Danes are in bold and marked with an asterisk (*). Kings of the Swedes are marked with a dagger (†). Superscript numbers before a name indicate in which books of Gesta Danorum the individual is mentioned.

⁽¹⁾ Humble

KEY

⁽¹⁾ Angul

⁽¹⁾ Dan*

⁽¹⁾ Grytha

Marriage or coupling

Parent and child

The Angles

⁽¹⁾ Humble*

⁽¹⁾ Lother*

⁽¹⁾ King of the Saxons

Succession by other or unclear means

⁽¹⁾ Roar

⁽¹⁾ Sigtryg, King of the Swedes†

⁽¹⁾ Skiold*

⁽¹⁾ Alfhild

⁽¹⁾ daughter of Roar

⁽¹⁾ Bess

⁽¹⁾ sister of Gram

⁽¹⁾ Gróa

⁽¹⁾ Gram*†

⁽¹⁾ Sumble, King of the Finns

⁽¹⁾ Wagnhofde

⁽¹⁾ Signe

⁽¹⁾ Henry, King of the Saxons

⁽¹⁾ Hakon, King of the Nitherians

⁽¹⁾ Hardgrep

⁽¹⁾ Swipdag*†, King of Norway

⁽¹⁾ sister of Guthorm

⁽¹⁾ Guthorm*

^(1,2,5) Hadding*

⁽¹⁾ Ragnhild

⁽¹⁾ Asmund†

⁽¹⁾ Gunnhild

⁽¹⁾ Guthorm

^(1,2) Ulfhild

⁽²⁾ Ubbe*

⁽¹⁾ Henry

⁽¹⁾ Uffe†

^(1,2) Hunding†

⁽²⁾ Thorhild

⁽²⁾ Scot

⁽¹⁾ daughter of Uffe

⁽²⁾ Ragnar†

⁽²⁾ Swanhwid

⁽²⁾ sisters of Swanhwid

⁽²⁾ Handwan

⁽²⁾ Thorwald

^(2,5) Frode*

⁽²⁾ daughter of Handwan

^(2,3) Hothbrodd†

⁽²⁾ Halfdan*

⁽²⁾ Ro

⁽²⁾ Skat

⁽²⁾ Thora

^(2,3) Helge*

⁽²⁾ Ro*

^(2,3) Athisl†

⁽²⁾ Urse

^(2,3) King Gewar

^(2,3) Rolf*† Krage

⁽²⁾ Rute

⁽²⁾ Bjarke

⁽²⁾ Skulde

^(2,3) Hiartuar†*

^(2,3) Hother†*

⁽³⁾ Nanna

⁽³⁾ Herlek

⁽³⁾ Gerit

⁽³⁾ former King of Britain

⁽³⁾ mother of the King of Britain

⁽³⁾ a slave

⁽³⁾ a bondmaid

⁽³⁾ Rorik*

⁽³⁾ Gerwendil

^(3,4) King of Britain

^(3,4) Queen of Britain

^(3,4) Gerutha

^(3,4) Horwendil

^(3,4) Feng

^(3,4) foster sister of Amleth

^(3,4) daughter of the King of Britain

^(3,4) Amleth

⁽⁴⁾ Hermutrude, Queen of Scotland

⁽⁴⁾ Wiglek*

⁽⁴⁾ son of Amleth

⁽⁴⁾ Wermund*

⁽⁴⁾ Frowin, governor of Sleswik

⁽⁴⁾ Uffe*, aka Olaf the Gentle

⁽⁴⁾ daughter of Frowin

⁽⁴⁾ Ket

⁽⁴⁾ Wig

⁽⁴⁾ Dan*

⁽⁴⁾ Hugleik*

⁽⁴⁾ Frode* the Vigorous

⁽⁴⁾ Dan*

⁽⁵⁾ Kraka

⁽⁵⁾ Ragnar

⁽⁵⁾ Brak

^(4,5) Fridleif* the Swift

⁽⁵⁾ Hun, King of the Huns

⁽⁵⁾ Hun

⁽⁵⁾ Gotar, King of Norway

⁽⁵⁾ Westmar

⁽⁵⁾ Koll

⁽⁵⁾ Gotwar

⁽⁵⁾ Roller

^(5,6) Erik† Shrewd-spoken

⁽⁵⁾ Gunwar the Fair

⁽⁵⁾ Alfhild

^(5,6) Frode*

⁽⁵⁾ Hanund

⁽⁵⁾ Grep (eldest of three)

⁽⁵⁾ 11 other sons (two named Grep)

⁽⁶⁾ Hythin, King of Tellemark

⁽⁵⁾ Alf

⁽⁵⁾ Eyfura

⁽⁵⁾ Arngrim

⁽⁶⁾ Grubb

⁽⁶⁾ Hiarn*

⁽⁶⁾ Amund, King of Norway

⁽⁶⁾ child of Hythin

⁽⁶⁾ Halfdan†

⁽⁵⁾ 12 sons, including Anganty

⁽⁶⁾ Ane

⁽⁶⁾ Juritha

⁽⁶⁾ Fridleif*

⁽⁶⁾ Frogertha

⁽⁶⁾ Hanef, King of Saxony

⁽⁶⁾ Swerting, King of Saxony

⁽⁶⁾ Olaf

⁽⁶⁾ Frode*

^(6,7) Siward†

⁽⁶⁾ sons of Swerting

⁽⁶⁾ sister of the sons of Swerting

^(6,7) Ingild*

⁽⁶⁾ Helga

⁽⁶⁾ Helge

⁽⁶⁾ Asa

^(6,7) Frode

^(6,7) Fridleif

^(6,7) Ingild

^(6,7) Olaf*

⁽⁷⁾ Karl, governor of Gothland

⁽⁷⁾ Ulfhild

⁽⁷⁾ Frode*

⁽⁷⁾ Hather, a chief

⁽⁷⁾ Harald*

⁽⁷⁾ Signe

⁽⁷⁾ Erik†

⁽⁷⁾ Thorhild

⁽⁷⁾ Halfdan*† Biargramm

⁽⁷⁾ Harald

⁽⁷⁾ Asmund

Kings of Norway

Name spellings are derived from Oliver Elton's 1905 translation, The First Nine Books of the Danish History of Saxo Grammaticus, via Wikisource.

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Gesta Danorum ("Deeds of the Danes") by Saxo Grammaticus is the most extensive, and most widely known Danish chronicle of Danish kings. It was written in Latin in the 12th century, and comprises 16 books, of which the first 9 relate to legendary kings leading up to Gorm the Old, and the remaining 7 are more recent and historical. The work is explicitly euhemeristic, repeatedly referring to certain individuals (including Odin, Baldr, and Thor) as mortal humans that people believed to be, and worshipped as, gods.

Saxo draws on many sources for this work. In several places where the sources appear contradictory, he will adapt more than one version at different places in the timeline, often creating multiple individuals where earlier stories had only one. For example, instead of a single king named Gorm the Old, Saxo says there were three different kings named Gorm. Sigurd Hring appears as two different kings, Ringo and Siwardus Ring.

More information Name, Consort(s) ...

Name	Consort(s)	Claim	Note(s)
Dan I	Grytha	Title created	Did not actually rule as a king, but merely as a governor.
Humble		Son of Dan I	Elected as a king after the death of his father, however, he proved a weak ruler and was soon deposed by his brother.
Lother		Son of Dan I	After deposing his brother, he resorted to tyranny and was killed while fighting a rebellion.
Skiold	Alfhild	Son of Lother	Became king when younger than fifteen, renowned hunter and fighter, extraordinarily tall. Subjugated the Alemanni in order to marry a Saxon princess.
Gram	Groa Signe	Son of Skiold	While his father was still alive, he invaded Sweden, and his father rewarded him by crowning him as co-ruler. Later, he was killed by Svipdagr, king of the Norwegians.
Svipdagr	Daughter of Gram and Groa	Son-in-law of Gram
Guthorm		Son of Gram Nephew of Svipdagr	Puppet king of Svipdagr.

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Other Danish kings include:

Hadingus
Frotho I
Haldanus I
Ro
Helgo
Rolvo Krake
Høtherus (and Balderus)
Rørikus (the grandfather of Hamlet)
Wiglecus
Wermundus
Uffo
Dan II
Huglecus
Frotho II
Dan III
Hiarnus^[6]
Fridlevus I
Frotho III
Fridlevus II
Frotho IV
Ingellus
Olavus I
Haraldus I
Frotho V
Haldanus II
Yngwin
Sywaldus I
Sygarus
Haraldus Hyldetan (Harald Wartooth)
Ringo
Olo
Omundus
Sywardus I
Iarmericus
Broderus
Sywaldus II
Snio
Biorn
Haraldus III
Gormo I
Gudfred
Olavus II
Hemmingus
Siwardus Ring
Regner Lothbrog
Siwardus III
Ericus I
Ericus II
Kanutus I
Frotho VI
Gormo II
Haraldus III
Gormo III

In Book VI of Gesta Danorum, Saxo also refers to a certain Hakon as the tyrant of Denmark when describing the early years of the champion Starkad. However, Hakon does not appear to fit into the timeline or family tree of Danish rulers as described in the rest of Gesta Danorum.

Gesta Danorum på danskæ

Gesta Danorum på danskæ, a work separate from Saxo's Gesta Danorum, is the earliest surviving chronicle of Danish kings that was written in the Danish language (then Old Norse). It is often referred to incorrectly as the Chronicon Lethrense in its English translation by Peter Tunstall.^[5] This work is based on the kings list from the Codex Runicus, and includes kings not in the Chronicon Lethrense, such as:^[7]

Wig
Aki
Hother of Saxland, son of Hodbrod and Hadding's daughter, as nearest heir.
Rorik Slengeborre or Rake
Wighlec
Wermund
Offe the Strong

Beowulf

The Old English epic poem Beowulf mentions several Danish kings, in particular Hroðgar, whose hall Heorot is the main setting of the tale.

Heremod, 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

Beowulf also refers to a rival family of rules called the Heaðobards, who are not kings of Denmark in this work but are depicted as kings of Denmark when they appear in later surviving works from the continent. These are:

Fróði, who killed or was killed by Healfdene
Ingeld, Fróði's son, who married Hroðgar's daughter Freawaru in an attempt to settle the feud between their families, but would turn against Hroðgar after the events of the poem

Widsith

Widsith is an Old English poem that survives in the 10th century Exeter Book, but may significantly predate it. The first of three thulas in the poem presents a list of kings, the most notable example of a king from each of several tribes. The thula says that Alewih was known as king of the Danes, and describes him as the bravest of all men listed but that he was defeated by Offa, ruler of the Angles. The thula also lists Sigehere as ruler of the "Sea-Danes".

Widsith also mentions Hroðulf ("Hroþwulf") and Hroðgar as an uncle and nephew who held the longest peace together, and Ingeld as a Heaðobard Viking ("wicinga cynn") whom they defeated at Heorot. None of these three are explicitly mentioned as Danish in Widsith, but appear as Danish in other works (see the section of Beowulf, above).

Gróttasöngr

Gróttasöngr ("Grótti's song") is an Eddic poem that survives only in certain manuscripts of Snorri Sturluson's Prose Edda, and as such as not always included in the Poetic Edda. The song is sung by two slave-girls, Fenja and Menja, who later identify themselves as the kin of bergrisi (jötnar). They are the slaves of King Fróði, son of Friðleifr. The poem itself does not specify that these men were kings of Denmark, but Snorri's prose introduction to the poem (in Skáldskaparmál) says that Friðleifr was the son of Skjöldr (himself a son of Odin), whose lands "were in what is now [i.e. in Snorri's time] called Denmark, but was then known as Gotland". The prose introduction also says that Fróði's reign coincided with the reign of Caesar Augustus and the birth of Christ; in Scandinavia, the resulting peace was ascribed to Fróði and known as Fróði's Peace.

A later stanza of Gróttasöngr prophesies that "Yrsa's son" (identified in other works as Hrólfr Kraki) would take vengeance on Fróði for the killing of Hálfdan (or, as plural, the half-Danes). (Halfdan is the name of several Danish kings in other sources.)

Skjöldr
Friðleifr
Fróði

Skjöldunga saga (partial list)

The kings of the saga of the Scylding family.

Scioldus
Fridleifus I
Frodo I
Herleifus
Havardus
Leifus
Herleifus
Hunleifus
Aleifus
Oddleifus
Geirleifus
Gunnleifus
Frodo II
Vermundus
Dan I
Dan II
Frodo III
Fridleifus II
Frodo IV
Ingjaldus
Helgo and Roas
Rolfo Krake
Hiorvardus
Rærecus

Sögubrot

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.

Ynglinga saga

The kings of the saga of the Ynglinga family.

Skjöldr
...
Frið-Fróði
...
Danr hinn mikilláti
Fróði hinn mikilláti eða friðsami
Hálfdan
Friðleifr
Áli hinn frækni
...
Fróði hinn frækni
...
Helgi Hálfdanarson
Hrólfr kraki

Histories of the Franks

The 6th century historian Gregory of Tours, in Book 3 of his Historia Francorum ("History of the Franks"), refers to a Danish king named Chlochilaicus, who led a raid into the Frankish Kingdoms during the reign of Theodericus I (511 to 534), and was killed in the counter-attack by Theodericus' son, Theodebertus.^[8] The 8th century Liber Historiae Francorum tells the same story, referring to the Danish King as Chochilaicus. (The same story also appears in the 7th or 8th century Liber Monstrorum and in the poem Beowulf, but in these works the raiding Viking king is named Hygelac, and described as King of the Geats rather than King of the Danes.)^[9]

Gesta Danorum refers to two characters named Huglecus, one as King of the Danes (see above), and another in Book VI as a King of the Irish who was attacked and defeated by the Danish forces of Hakon and Starkad.

The Life of Willibrord

The Vita Willibrordi archiepiscopi Traiectensis, or The Life of Willibrord, Archbishop of Utrecht, is a late 8th century hagiography of Willibrord, written by the Northumbrian scholar Alcuin. This work relates how Willibrord became a missionary to the Danes and met their ruler, Ongendus, described as "a man more savage than any wild beast and harder than stone".^[10]

Royal Frankish Annals

The Royal Frankish Annals are a series of Latin annals of the Carolingian dynasty year-by-year between 741 to 829. Several annals refer to kings of the Danes, as follows:

Sigfred ("Sigifrid"): In 782, King Sigfred sends a group of "Nordmanni", Halptani and his companions, to a synod held by Charlemagne. (Sigfred is not explicitly referred to as a king of the Danes in this work, but the others mentioned are.)
Gudfred ("Godofrid"): Gudfred was mentioned as King of the Danes in the annals of 804, 808, 809, and 810. His reign was characterised by a worsening relationship and finally conflict with Charlemagne's Franks. Gudfred was killed by one of his own companions in 810.
Hemming: Hemming was the son of Gudfred's brother, and became king in 810. He made peace with Charlemagne in 811. In 812, he was found dead.
Sigfred ("Sigifrid") and Anulo: Two rival claimants to the Danish throne in 812, Sigfred was a nephew of Gudfred and Anulo was a nephew of Harald ("Heriold"). Neither succeeded to the throne as both were killed in combat, but Anulo's faction won and the throne passed to his brothers Harald and Reginfrid.
Reginfrid: Reginfrid was co-king of Denmark with his brother Harald from 812. They petitioned the Emperor (Louis the Pious) to return their brother Hemming, but after he was returned in 813 they were attacked by Danish forces of the sons of Gudfred and forced into exile. In 814 they returned to retake the kingdom, but Reginfrid was killed.
Harald ("Hariold"): Harald initially ruled with his brother Reginfrid from 812. After being forced out of Denmark, and the death of his brother in 814, Harald sought refuge and support from the Emperor. He continued to harry his rivals, the sons of Gudfred, and in 817 they contacted the Emperor offering peace in exchange for Harald; the Emperor refused. The Emperor helped him retake Denmark in 819 (two sons of Gudfred defected to him). He remained in conflict with them as mentioned in 821, 822 and 823. In 826, he was baptised as a Christian in St. Alban's. He was forced out of the country in 827.
Horik ("Hohric"): One of the sons of Gudfred who took control of Denmark in 813 and battled with Harald for it until 827, Horik is only mentioned in the annal for 827, before the annals conclude in 829.

Vita Ansgarii

Vita Ansgarii is a 9th century hagiography of saint Ansgar, written by the East Frankish archbishop Rimbert. Vita Ansgarii mentions two Danish kings visited by Ansgar:

Horic the elder (in chapters XXIV, XXVI and XXXI), and
Horic the younger (in chapters XXXI and XXXII).

Although both kings were pagan, they had good relations with Ansgar and permitted the worship and preaching of Christianity in Denmark (although when the younger Horic first took power, a certain headman had urged him to persecute the Christians).^[11]

Historia Regum Britanniae

Book III of the 12th century Historia Regum Britanniae by Geoffrey of Monmouth refers to a King of the Dacians named Guichtlac. As mentioned above in the section on Chronicon Lethrense, the Danes and Dacians had been conflated by European historians since at least the works of Dudo of Saint-Quentin over a century earlier. In Geoffrey's tale, Guichtlac had been in love with the daughter of Elsingius the King of Norway, but instead she married Brennius, then King of Northumberland and the brother and rival of Belinus, King of the Britons. After a sea battle, Guichtlac and the lady were washed up in Britain and captured by Belinus. After Brennius defeated Belinus in battle and became King of the Britons, Guichtlac promised to submit Dacia (Denmark) to Brennius and pay yearly tribute if he was given leave to return to Dacia with his mistress, which was granted.

Others

Eric the Child (Horik/Erik Barn): 854- after 864, dead or deposed by 873
Sigurd Snake-in-the-Eye (Sigurd Orm i Øje): mention 873, d. 903, do coin money by East Anglia
- Halfdan (Halvdan): mention 873, d. 876/877

Many kings are mentioned by multiple sources, but are for various reasons still considered more legendary than historical kings of Denmark

Harthacnut (Hardeknud) (c. 916 – c. 936), 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 Gnupasson, either deposed c. 916 by Harthacnut or contemporary, depending on sources. Likely had base in Schleswig, but the extent of his realm is unknown. Son of Gnupa.
Gnupa (early 900s). Father of Sigtrygg. According to one source he shared power with his brother Gyrd. According to the Saga of Olaf Tryggvason, he was defeated as one of the minor border kings by Gorm when he united Denmark, though that conflicts with Gnupa's son being deposed by Gorm's father according to other sources.
Olof the Brash conquered Denmark (or part of Denmark) c. 900.
Helgi, supposedly deposed by Olaf the Brash.
Sigurd Snake-in-the-Eye (Sigurd Orm-i-øje or Snogeøje) became king of Zealand and Scania according to the sagas, perhaps correctly named Sigfred and co-ruling as king of Denmark with his brother Halfdan Ragnarsson (d. 877). Mentioned by Chronicon Roskildense and Ragnarssona þáttr. Son of Ragnar Lodbrok.
Halfdan Ragnarsson (c. 871 – 877), son of Ragnar Lodbrok and older brother of Sigurd Snake-in-the-Eye. Leader of the so called Great Heathen Army of the Anglo-Saxon sources, in 870 and 871. King Bagsecg joined him to become the co-leader of the Great Summer Army of 870 but Bagsecg was killed in battle with the English in January 871. Halfdan succeeded Bagsecg as king of Jutland.
Bagsecg, Danish king who came to England and was killed in 871.
Horik II, king from about 854 until about 870.
Horik I, co-ruler of Denmark from 813, the sole king of Denmark c. 828 to 854. Son of Gudfred.
Harald Klak, 812 to 813 and 819 to 827, a period of civil war with the sons of Gudfred. Nephew of an earlier Harald.
Hemming, c. 810 to c. 812. Nephew of Gudfred. Brother of Ragnvald, Håkon and Angantyr.
Gudfred (Godfred or Gøtrik), a Danish king c. 804 to 810. Said to be father of Ogier the Dane (Holger Danske); possibly the son of Sigfred.
Ragnar Lodbrok was a legendary king, allegedly flourishing before 865. He is mentioned in multiple sources, but the sources are wildly inconsistent. There is no historical record of anyone named Ragnar ruling Denmark in the 9th century. However his sons Halfdan Ragnarsson and Sigurd Snake-In-the-Eye may have become kings of Denmark, while his son Bjorn Ironside became king of Sweden and Uppsala according to various late sagas.
Sigfred, Danish king c. 770 to c. 804. Possibly the historical basis for Sigurd Hring. Reported to have assisted the Saxons against Charlemagne.
Harald Wartooth (Harald Hildetand), legendary king of Denmark, Sweden and parts of Norway, sometimes assigned to c. 715 to c. 770. Mentioned in multiple sources. According to one source his conquests reached as far as the Mediterranean. Said to be grandfather of Ragnar Lodbrok.
Ongendus was a king of the Danes, reigning c. 710, the first Danish king known from contemporary literature.
Randver, sometimes assigned to the early 700s. Son of Valdar (or Radbard) according to late sagas; fell in England.
Valdar, sometimes assigned to the early 700s. Son-in-law of Ivar Vidfamne and sub-king in Denmark according to the late sagas.
Ivar Vidfamne, sometimes assumed to have died in c. 700. The Viking sagas say that Ivar Vidfamne ruled over most of Denmark, Sweden, Saxland and even parts of England.

Rig and Scylding line

Early kings of the Rig and Scylding lines, mentioned by multiple sources

Dan mikilláti, son of Danp, 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 Halga

After Hrólf Kraki no two sources give the same succession.

[1]
Sven Estridsen (in Adam of Bremen), by Mischa Hooker of Augustana College, with text and translation
[2]
Gorm of Denmark and his immediate predecessors based on the earliest authorities, compiled by Stewart Baldwin
[3]
Latin text of Adam of Bremen's Gesta Hammburgensis ecclesiae pontificum from B. Schmeidler, 3rd ed., MGH SRG 2 (1917)
[4]
History of the Archbishops of Hamburg-Bremen, English translation with an introduction and notes by Francis J. Tschan. Columbia University Press. New York (1959).
[5]
Chronicon Lethrense, with translation and commentary by Mischa Hooker of Augustana College
[6]
Saxo Grammaticus, ed. Hilda Ellis Davidson, p. 165.
[7]
English translation of Gesta Danorum på danskæ (as The Chronicle of the Kings of Lejre), by Peter Tunstall.
[8]
Gregory of Tours, Decem Libri Historiarum III 3 at The Latin Library
[9]
Explanatory notes to Beowulf, "1204-1216, 2355f., 2502-2509, 2915-2920: Hygelac's raid on Frisia", including Historia Francorum, Liber Historiae Francorum and Liber Monstrorum in Latin and in English translation
[10]
Medieval Sourcebook: Alucin (735-804): The Life of Willibrord, c.796
[11]
Medieval Sourcebook: Rimbert: Life of Anskar, the Apostle of the North, 801-865

[1] [1]
Sven Estridsen (in Adam of Bremen), by Mischa Hooker of Augustana College, with text and translation

[2] [2]
Gorm of Denmark and his immediate predecessors based on the earliest authorities, compiled by Stewart Baldwin

[3] [3]
Latin text of Adam of Bremen's Gesta Hammburgensis ecclesiae pontificum from B. Schmeidler, 3rd ed., MGH SRG 2 (1917)

[4] [4]
History of the Archbishops of Hamburg-Bremen, English translation with an introduction and notes by Francis J. Tschan. Columbia University Press. New York (1959).

[CL-5] [5]
Chronicon Lethrense, with translation and commentary by Mischa Hooker of Augustana College

[6] [6]
Saxo Grammaticus, ed. Hilda Ellis Davidson, p. 165.

[7] [7]
English translation of Gesta Danorum på danskæ (as The Chronicle of the Kings of Lejre), by Peter Tunstall.

[8] [8]
Gregory of Tours, Decem Libri Historiarum III 3 at The Latin Library

[9] [9]
Explanatory notes to Beowulf, "1204-1216, 2355f., 2502-2509, 2915-2920: Hygelac's raid on Frisia", including Historia Francorum, Liber Historiae Francorum and Liber Monstrorum in Latin and in English translation

[10] [10]
Medieval Sourcebook: Alucin (735-804): The Life of Willibrord, c.796

[11] [11]
Medieval Sourcebook: Rimbert: Life of Anskar, the Apostle of the North, 801-865

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

Adam of Bremen

Chronicon Lethrense

Sven Aggesen

Gesta Danorum

Gesta Danorum på danskæ

Beowulf

Widsith

Gróttasöngr

Skjöldunga saga (partial list)

Sögubrot

Ynglinga saga

Histories of the Franks

The Life of Willibrord

Royal Frankish Annals

Vita Ansgarii

Historia Regum Britanniae

Others

Rig and Scylding line

Adam of Bremen

Chronicon Lethrense

Sven Aggesen

Gesta Danorum

Gesta Danorum på danskæ

Beowulf

Widsith

Gróttasöngr

Skjöldunga saga (partial list)

Sögubrot

Ynglinga saga

Histories of the Franks

The Life of Willibrord

Royal Frankish Annals

Vita Ansgarii

Historia Regum Britanniae

Others

Rig and Scylding line

Danish sources

Anglo-Saxon sources

Icelandic sources

Other sources

Multiple sources

See also

References