The relationship between Sigifrid and other Danish leaders such as his apparent successor Godofrid / Godfred is unclear. There have been speculative attempts to link Sigifrid (or a later Sigifrid who 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." (E.g., H. Howorth, "Harald Fairhair and His Ancestors," Saga-Book of the VIking-Society 9, pp. 61-66). While some names seem authentically related, equations are elusive, and no historical conclusions are agreed on.
For analysis of Sigifrid's role in historical context, see D. Melleno, Before They Were Vikings (Diss. Berkeley 2014), pp. 28ff.; K. L. Maund, "'A Turmoil of Warring Princes': Political Leadership in Ninth-Century Denmark," The Haskins Society Journal 1994: 29-47.
Tunc domnus Carolus rex synodum publicum habuit ad Paderbrunnen prima vice. Ibique convenientes omnes Franci, et ex omni parte Saxoniae undique Saxones convenerunt, excepto quod Widochindis rebellis extitit cum paucis aliis: in partibus Nordmanniae confugium fecit una cum sociis suis.
Then the lord king Charles held the general assembly at Paderborn for the first time. All the Franks gathered there and, from every part of Saxony whatsoever, the Saxons too, with the exception of Widukind, who, with a few others, was in rebellion and took refuge in Nordmannia with his companions.
… ad locum, qui Padrabrunno vocatur, generalem populi sui conventum in eo habiturus cum ingenti exercitu in Saxoniam profectus est. Eo cum venisset, totum perfidae gentis senatum ac populum, quem ad se venire iusserat, morigerum ac fallaciter sibi devotum invenit. Nam cuncti ad eum venerunt praeter Widokindum, unum ex primoribus Westfalaorum, qui multorum sibi facinorum conscius et ob id regem veritus ad Sigifridum Danorum regem profugerat.
(The king) … moved into Saxony with a huge army to the place called Paderborn to hold the general assembly of his people there … He had ordered all the magnates [senatusJ and people of that perfidious race to come to him and when he arrived at Paderborn found them there, obedient and pretending devotion to him. For they all came to him with the exception of Widukind, one of the primores of the Westphalians, who, conscious of his numerous crimes, had fled to Sigfred, king of the Danes.
Tunc domnus Carolus rex, Renum transiens ad Coloniam et synodum tenuit, ubi Lippia consurgit; ibique omnes Saxones venientes, excepto rebellis Widochindus. Etiam illuc convenerunt Nordmanni missi Sigifridi regis, id est Halptani cum sociis suis; similiter et Avari illuc convenerunt, missi a cagano et iugurro. Ibi peracto placito reversus est domnus Carolus rex in Franciam. Et cum reversus fuisset, statim iterum Saxones solito more rebellati sunt, suadente Widochindo.
Then the lord king Charles, setting out on an expedition, crossed the Rhine at Cologne and held the assembly at the source of the Lippe. All the Saxons except Widukind the rebel came there. Northmen, Halptani and his companions, the missi of king Sigfred, also came there, as did likewise Avars sent by the khagan and the jugur. When the assembly there was over the lord king Charles returned to Francia. And immediately after his return, the Saxons, in their customary fashion, again rebelled, at the instigation of Widukind.
… generalem conventum habendum censuit. Traiectoque apud Coloniam Rheno, cum omni Francorum exercitu ad fontem Lippiae venit, et castris positis, per dies non paucos ibidem moratus est. Ubi inter cetera negotia etiam legatos Sigifridi regis Danorum, et quos ad se Caganus et Iugurrus principes Hunorum velut pacis causa miserunt, et audivit et absolvit. Cumque conventu completo trans Rhenum in Galliam se recepisset, Widokindus, qui ad Nordmannos profugerat, in patriam reversus vanis spebus Saxonum animos ad defectionem concitavit.
… he decided to … hold the general assembly there … He crossed the Rhine at Cologne and came with the whole army of the Franks to the source of the Lippe, where he set up camp. He stayed there some time and dealt with various matters; among other things, he gave audience and leave to depart to legates from Sigfred, king of the Danes, and to those sent to him, supposedly in the cause of peace, by the khagan and the jugur, princes of the Huns. After the assembly had been concluded and he had recrossed the Rhine into Gaul, Widukind, who had taken refuge with the Northmen, returned to his homeland and stirred up the passions of the Saxons with vain hopes so that they rebelled.
Saxones … reddiderunt omnes malefactores illos, qui ipsud rebellium maxime terminaverunt, ad occidendum ĪĪĪĪ D; quod ita factum est, excepto Widochindo, qui fuga lapsus est partibus Nordmanniae.
The Saxons … handed over all the evil-doers - with the exception of Widukind, who escaped by flight to Nordmannia - bearing the greatest responsibility for that rebellion, 4,500 in number, to be put to death. And this sentence was carried out.
Et cum omnes Widokindum huius sceleris auctorem proclamarent, eum tamen tradere nequirent, eo quod is re perpetrata ad Nordmannos se contulerat, ceterorum, qui persuasioni eius morem gerentes tantum facinus peregerunt, usque ad quattuor milia D traditi et super Alaram fluvium in loco, qui Ferdun vocatur, iussu regis omnes una die decollati sunt.
And since they all declared that Widukind was the author of this wickedness but were unable to deliver him up in view of the fact that he had taken himself off to the Northmen once the deed had been done, no fewer than 4500 of the others, those who had fallen in with his promptings and committed such a gross outrage, were handed over and at the place on the river Aller called Verden, at the king's command, all beheaded in a single day.
… Saxones Transalbiani occasionem nancti legatos regis, qui ad eos ob iustitias faciendas missi erant, conprehensos interficiunt, paucis eorum quasi ad redimendum reservatis, trucidantes cum caeteris et Godescalcum regis legatum, quem ille ante paucos dies ad Sigifridum regem Danorum miserat. Is cum eodem tempore reverteretur, ab huius seditionis auctoribus interceptus atque occisus est.
… an opportunity presented itself to the Saxons across the Elbe. They seized the king's legates who had been sent to them to do justice and put all but a few, whom they kept for ransom, to death. Along with the rest they slew also Godescal, a royal legate whom the king had sent a few days earlier to Sigfred, king of the Danes; since he was returning at this time he was intercepted by the authors of this sedition and killed.
Ipse medio mense Martio Aquisgrani palatio digrediens, litus oceani Gallici perlustravit, in ipso mari, quod tunc piratis infestum erat, classem instituit, praesidia disposuit …
He himself left the palace at Aachen in mid-March and toured the coastal region adjoining the Gallic ocean; he created a fleet upon this sea since it was infested with pirates at that time, organised defences …
Redeunte verna temperie medio fere Martio rex Aquisgrani digressus litus oceani Gallici perlustravit et in ipso mari, quod tunc piratis Nordmannicis infestum erat, classem instituit, praesidia disposuit …
With the return of spring's mildness, the king left Aachen about mid-March and toured the coastal region adjoining the Gallic ocean; he created a fleet upon this sea, since it was infested with pirates from Nordmannia at that time, organised defences …
In the persona of the Emperor Charlemagne, he asks Paul which of these three disagreeable things he'd rather do (translation adapted from E. Christiansen, Norsemen in the Viking Age, p. 118):
Si cupis ingenti ferri tu pondere frangi,
Carceris aut saevo fessus recubare sub antro,
Aut si pompiferi Sigifrit perpendere vultum,
Impia pestiferi nunc regni sceptra tenentis,
Ut valeas illum sacro perfundere fonte,
Vis, qui te cernens vita spoliabit et arte.
If you desire to be broken by a huge weight of iron, or lie down tired down in the harsh cavern of a prison; or if you are willing to look at the face of the grandiose Sigifrit (now holding sway in a noxious kingdom), with a view to baptize that fellow from a holy font, who will rob you on sight of life and learning.
[Interesting inter alia for the names of gods Thor (Thonar) and Odin (Waten) mentioned.]
Si satagam Sigifrid truculentum cernere vultum,
Vix perpendo aliquod utilitatis opus.
Ille caret Latiis indocto corde loquellis,
Illius est minime cognita lingua mihi:
Simia setiferumve brutum pecus esse putabor,
Deridetque meum stulta caterva caput.
Sit licet hirsutus hirtisque simillimus hircis,
Iuraque det hedis imperitetque capris,
Sunt illi invalidae pavitanti in pectore vires,
Nam nimium vestrum nomen et arma timet.
Is scierit vestris si me de civibus unum,
Audebit minimo tangere nec digito.
Tunc nec iners cupido vitam mihi tollit et artem,
Illum nec palmis abluet unda meis.
Quin potius properet, vestra et vestigia lambat,
Cumque suo ponat crimina crine simul.
Caelitus et quoniam est vobis conlata potestas,
Tinguatur vestris purificandus aquis.
Sin minus, adveniat manibus post terga revinctis,
Nec illi auxilio Thonar et Waten erunt.
If I should busy myself about seeing the face of ferocious Sigifrit, I scarcely weigh it as a useful task. That man lacks Latin eloquence, with his uneducated heart; his tongue is not at all known to me. I will be considered to be an ape or a bristly brute beast of burden, and a stupid crowd will scoff at my head. Though he is hairy and very like the shaggy billy-goats, gives laws to kids and rules over he-goats, the power in his trembling breast is strengthless, for he is very much afraid of your name and your arms. If he knows that I am one of your countrymen, he will not even dare to touch me with his little finger. Then neither does sluggish desire lift up my life and art, nor will water wash that man from my hands. Nay rather, let him hurry up and lick your feet, and lay down his lacks along with his locks. And since power was conferred on you from heaven, let him be washed for purification in your waters. If not, he will arrive with his hands tied behind his back, and Thor and Odin will be no help to him.