The relationship between Godofrid and his apparent predecessor Sigifrid / Sigfred is unclear. There have been speculative attempts to link Sigifrid (or a later Sigifrid, Godofrid's nephew, who is said to have clashed for power with one Anulo [Latin for "ring"?], nephew of one "Harald") with the legends about Sigurd Hring and his uncle and opponent, Harald Wartooth, which culminate in the epic "Battle of Brávellir." Similarly, some connect Godofrid with a legendary Gudrød known from sagas (e.g., H. Howorth, "Harald Fairhair and His Ancestors," Saga-Book of the VIking-Society 9, pp. 64-86, in great detail). It is clear, at least, that the Gøtrik described in the last part of Book 8 of Saxo Grammaticus' Gesta Danorum is largely based on historical information about Godofrid; however, historical ties with saga and legend are otherwise controversial.
For analysis in historical context, see D. Melleno, Before They Were Vikings (Diss. Berkeley 2014), passim, especially pp. 43ff.; K. L. Maund, "'A Turmoil of Warring Princes': Political Leadership in Ninth-Century Denmark," The Haskins Society Journal 1994: 29-47; in particular, the idea that "multiple leadership" seems to have been the norm is important -- as Maund points out (32), "it is almost always the case that political power was held by more than one man at a time and, even when we know the name of only one leader, it is dangerous in the extreme to think in terms of 'monarchy.'" At least in his interactions with the Frankish kingdom, however, Godofrid appears as a strong and confident leader presenting a unified and agressive front toward Charlemagne. After his death, the sources present a wild proliferation of rivals for power, presumably all related in various ways, with major factions emerging around the sons of Godofrid on the one hand and Harald Klak and his brothers on the other; Harald appealed for help from Francia, and was famously baptized at Mainz in 826, although this did not end the jockeying for position over political control in Denmark -- yet it did result in the mission of Ansgar to Scandinavia.
Besides the accounts in Einhard's Life, most of the contemporary information known about Godofrid comes from the Annales regni Francorum, which are therefore excerpted here below. Information about Danish figures and events from Godofrid's time and onwards is found also in Adam of Bremen's History (for the early period mostly drawn from various annals and hagiographies).
Aestate autem in Saxoniam ducto exercitu omnes, qui trans Albiam et in Wihmuodi habitabant, Saxones cum mulieribus et infantibus transtulit in Franciam et pagos Transalbianos Abodritis dedit. Eodem tempore Godofridus rex Danorum venit cum classe sua necnon et omni equitatu regni sui ad locum, qui dicitur Sliesthorp, in confinio regni sui et Saxoniae. Promisit enim se ad conloquium imperatoris venturum, sed consilio suorum territus propius non accessit, sed, quicquid voluit, per legatos mandavit. Nam imperator super Albiam fluvium sedebat, in loco, qui dicitur Holdunsteti, et missa ad Godofridum legatione pro perfugis reddendis medio Septembrio Coloniam venit …
But in the summer [Charles] led an army into Saxony and transported all the Saxons who dwelt beyond the Elbe and in Wihmodia, together with their wives and children, to Francia, giving the districts across the Elbe to the Abodrites. At this same time Godfred, king of the Danes, came with his fleet and all the horsemen of his kingdom to the place called Sliesthorp [SchleswigJ, on the border of his kingdom and Saxony. Although he promised to come to a conference with the emperor, he was alarmed by his men's counsel and came no nearer, instead letting his wishes be known through legates. The emperor, who was encamped at the place called Hollenstedt on the river Elbe, sent a legation to Godfred with a view to the return of fugitives. He arrived in Cologne in mid-September …
Et quia nuntiabatur Godofridum regem Danorum in Abodritos cum exercitu traiecisse, Carlum filium suum ad Albiam cum valida Francorum et Saxonum manu misit, iubens vesano regi resistere, si Saxoniae terminos adgredi temptaret. Sed ille stativis per aliquot dies in litore habitis, expugnatis etiam et manu captis aliquot Sclavorum castellis cum magno copiarum suarum detrimento reversus est. Nam licet Drasconem ducem Abodritorum popularium fidei diffidentem loco pepulisset, Godelaibum alium ducem dolo captum patibulo suspendisset, Abodritorum duas partes sibi vectigales fecisset, optimos tamen militum suorum et manu promptissimos amisit et cum eis filium fratris sui nomine Reginoldum, qui in obpugnatione cuiusdam oppidi cum plurimis Danorum primoribus interfectus est. Filius autem imperatoris Carlus Albiam ponte iunxit et exercitum, cui praeerat, in Linones et Smeldingos, qui et ipsi ad Godofridum regem defecerant, quanta potuit celeritate transposuit populatisque circumquaque eorum agris transito iterum flumine cum incolomi exercitu in Saxoniam se recepit.
And since it was reported that Godfred, king of the Danes, had crossed into the territory of the Abodrites with an army, he sent his son Charles to the Elbe with a strong force of Franks and Saxons and orders to resist the insane king should he attempt an attack upon the frontiers of Saxony. But after Godfred had maintained camp on the coast for some time and also attacked and captured by force of arms a number of the Slavs' castella, he returned home. His force had suffered heavy casualties, for although he had driven out Thrasco, dux of the Abodrites, who despaired of the people's loyalty, had captured another dux, Godelaib, by treachery and hanged him from a gallows, and had made two thirds of the Abodrites his tributaries, he had yet lost the best and most fearless of his soldiers and with them his brother's son, Reginald, who was killed together with a great many of the primores of the Danes at the siege of a certain fortress [oppidum]. Moreover, the emperor's son Charles threw a bridge across the Elbe and with all the speed he could muster moved the army he commanded across it against the Linones and Smeldingi, who had also defected to king Godfred. He laid waste their fields far and wide and then recrossed the river, returning to Saxony with his army unscathed.
Erant cum Godofrido in expeditione praedicta Sclavi, qui dicuntur Wilzi, qui propter antiquas inimicitias, quas cum Abodritis habere solebant, sponte se copiis eius coniunxerunt; ipsoque in regnum suum revertente, cum praeda, quam in Abodritis capere potuerunt, et ipsi domum regressi sunt. Godofridus vero, priusquam reverteretur, distructo emporio, quod in oceani litore constitutum lingua Danorum Reric dicebatur et magnam regno illius commoditatem vectigalium persolutione praestabat, translatisque inde negotiatoribus, soluta classe ad portum, qui Sliesthorp dicitur, cum universo exercitu venit. Ibi per aliquot dies moratus limitem regni sui, qui Saxoniam respicit, vallo munire constituit, eo modo, ut ab orientali maris sinu, quem illi Ostarsalt dicunt, usque ad occidentalem oceanum totam Egidorae fluminis aquilonalem ripam munimentum valli praetexeret, una tantum porta dimissa, per quam carra et equites emitti et recipi potuissent. Diviso itaque opere inter duces copiarum domum reversus est.
With Godfred on the aforesaid expedition were the Slavs who are called Wiltzites; they had joined his forces voluntarily out of the ancient enmity which existed between them and the Abodrites. When he went back to his kingdom they returned to their homes also, with the booty which they had been able to seize from the Abodrites. Before Godfred returned home, however, he destroyed the trading-place on the sea-coast which was called Reric in the Danes' tongue and conferred great benefit on his kingdom through the payment of tolls. He transported the merchants from there, had his fleet set sail and arrived with his entire army at the port called Sliesthorp [Schleswig]. Staying there for some time, he decided to protect the frontier-area of his kingdom facing Saxony with a rampart in such a way that a protective bulwark, broken by a single gateway through which wagons and horsemen could be let out and admitted, would form a border from the gulf on the eastern seaboard which they call Ostersalt [the Baltic) along the entire length of the northern bank of the river Eider as far as the western ocean. Once he had apportioned the work among the duces of his troops, he returned home.
Interea Godofridus rex Danorum per negotiatores quosdam mandavit, se audisse, quod imperator ei fuisset iratus, eo quod in Abodritos anno superiore duxit exercitum et suas ultus est iniurias, addens velle se purgare ab eo, quod ei obiciebatur; foederis inruptionem ab illis primo fuisse inchoatam. Petebat etiam, ut conventus comitum imperatoris atque suorum iuxta terminos regni sui trans Albim fieret, in quo res invicem gestae proferri et emendatione digna inter partes enumerari potuissent. Non abnuit imperator; colloquiumque trans Albiam habitum cum primoribus Danorum in loco, qui dicitur ...., multisque hinc et inde prolatis atque enumeratis rebus negotio penitus infecto discessum est. Thrasco vero dux Abodritorum, postquam filium suum postulanti Godofrido obsidem dederat, collecta popularium manu et auxilio a Saxonibus accepto vicinos suos Wilzos adgressus agros eorum ferro et igni vastat; regressusque domum cum ingenti praeda accepto iterum a Saxonibus validiori auxilio Smeldingorum maximam civitatem expugnat atque his successibus omnes, qui ab eo defecerant, ad suam societatem reverti coegit.
Meanwhile Godfred, king of the Danes, sent word by some merchants that he had heard that the emperor was angry with him because he had led an army against the Abodrites the year before and avenged the injuries done him. He added that he wished to clear himself of what was alleged against him; the first breach of the treaty had originated with them. He asked, further, that a meeting of his counts and the emperor's should take place beyond the Elbe, near the frontier of his kingdom, where what had been done on both sides could be brought up between the parties and matters which it would be appropriate to put right could be detailed. The, emperor did not reject this request and the conference with the primores of the Danes was held across the Elbe in the place called Badenfllot [probably Be1denfleth]. Many matters were brought up and detailed on both sides, but when they separated the business was left entirely unsettled. However, Thrasco, dux of the Abodrites, after he had given his son as a hostage to Godfred as the king required, gathered a force of his countrymen together and, with help from the Saxons, attacked his neighbours, the Wiltzites; he laid their territory waste, with fire and sword and returned home with immense booty. Then, with further aid from the Saxons, more than before, he captured the greatest civitas of the Smeldingi. By these successes he forced all those who had defected from him to become his allies again.
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Imperator autem, cum ei multa de iactantia et superbia regis Danorum nuntiarentur, statuit trans Albiam fluvium civitatem aedificare Francorumque in ea ponere praesidium. Cumque ad hoc per Galliam atque Germaniam homines congregasset armisque ac ceteris ad usum necessariis rebus instructos per Frisiam ad locum destinatum ducere iussisset, Thrasco dux Abodritorum in emporio Reric ab hominibus Godofridi per dolum interfectus est. Sed imperator, postquam locus civi*tati constituendae fuerat exploratus, Egbertum comitem huic negotio exsequendo praeficiens Albim traicere et locum iussit occupare. Est autem locus super ripam Sturiae fluminis, vocabulo Esesfelth, et occupatus est ab Egberto et comitibus Saxonicis circa Idus Martias et muniri coeptus.
The emperor decided, however, in view of the many reports which had reached him about the bragging and arrogance of the king of the Danes, that he would build a civitas across the river Elbe and install a garrison of Franks in it. And after he had gathered men from throughout Gaul and Germany for this purpose and ordered them, furnished with arms and the other equipment which they needed for the task, to be taken to the appointed place through Frisia, Thrasco, dux of the Abodrites, was treacherously killed by Godfred's homines at the trading-place of Reric. Neverthless, once the site for the civitas which was to be established had been confirmed, the emperor put count Egbert in charge of the execution of the project and commanded him to cross the Elbe and occupy the place. This lies on the bank of the river Stor and is called Esesfelth [ItzehoeJ. Egbert and the Saxon counts took possession of the place about the middle of March and began its fortification.
Imperator vero Aquisgrani adhuc agens et contra Godofridum regem expeditionem meditans nuntium accepit, classem ducentarum navium de Nordmannia Frisiam appulisse totasque Frisiaco litori adiacentes insulas esse vastatas iamque exercitum illum in continenti esse ternaque proelia cum Frisonibus commisisse Danosque victores tributum victis inposuisse et vectigalis nomine centum libras argenti a Frisonibus iam esse solutas, regem vero Godofridum domi esse. Et revera ita erat. Qui nuntius adeo imperatorem concitavit, ut missis in omnes circumquaque regiones ad congregandum exercitum nuntiis ipse sine mora palatio exiens primo quidem classi occurrere, deinde transmisso Rheno flumine in loco, qui Lippeham vocatur, copias, quae nondum convenerant, statuit operiri; ubi dum aliquot dies moraretur, elefans ille, quem ei Aaron rex Sarracenorum miserat, subita morte periit. Congregatis tandem copiis, quanta potuit celeritate ad Alaram fluvium contendit castrisque iuxta confluentem eius, quo Wisurae flumini coniungitur, positis minarum Godofridi regis praestolatur eventum. Nam rex ille vanissima spe victoriae inflatus acie se cum imperatore congredi velle iactabat.
And while still at Aachen and pondering a campaign against king Godfred, the emperor was told that a fleet of 200 ships from Nordmannia had sailed to Frisia, that all the islands off the Frisian coast had been devastated, that the army was already on the mainland and had fought three battles with the Frisians, that the victorious Danes had imposed tribute on the vanquished, that the Frisians had already paid 100 pounds of silver under title of tribute, but that king Godfred was at home. Such was indeed the situation. So enraged by this news was the emperor that he sent men out into all the regions far and wide to gather an army and himself straightway set out from the palace, deciding first to join up with the fleet and then to cross the river Rhine at the place called Lippeham and await the troops who had not yet assembled. And while he stayed there for a time the elephant sent to him by Aaron, rex of the Saracens, suddenly died. When the troops had finally gathered, he marched as rapidly as possible to the river Aller, set up camp by its confluence with the river Weser and awaited the outcome of king Godfred's threats. For that king, puffed up with the emptiest hopes of victory, was bragging that he meant to engage the emperor in pitched battle.
Sed dum imperator memorato loco stativa haberet, diversarum rerum nuntii ad eum deferuntur. Nam et classem, quae Frisiam vastabat, domum regressam et Godofridum regem a quodam suo satellite interfectum, castellum vocabulo Hohbuoki Albiae flumini adpositum, in quo Odo legatus imperatoris et orientalium Saxonum erat praesidium, a Wilzis captum et Pippinum filium eius, regem Italiae, VIII. Idus Iulii de corpore migrasse duasque legationes de diversis terrarum partibus, unam de Constantinopoli, alteram de Corduba, pacis faciendae causa adventare narratur. Quibus ille acceptis disposita pro temporis conditione Saxonia domum revertitur ...
But while the emperor maintained his quarters at the place mentioned, various matters were reported to him: the fleet which had been devastating Frisia had returned home; king Godfred had been killed by someone from his retinue; the castellum lying on the river Elbe by the name of Hohbeck, which contained a garrison of east Saxons and the emperor's legate, Odo, had been captured by the Wiltzites; his son Pippin, king of Italy, had departed this life on 8 July; and two legations had arrived from different parts of the world to make peace, one from Constantinople, the other from Cordova. After receiving these reports and arranging matters in Saxony to suit the circumstances of tne time, be returned home ...
Godofrido Danorum rege mortuo Hemmingus filius fratris eius in regnum successit ac pacem cum imperatore fecit.
After the death of Godfred, king of the Danes, Hemming, his brother's son, succeeded to the kingship and made peace with the emperor.