As I continue reading through some of the early sources for Anglo-Saxon genealogy, I came across an interesting article by Timothy Bolton on the paternal ancestry of Earl Waltheof. (Nottingham Medieval Studies, 51:41-71) In it he summarized a collection of manuscripts that together form part of Douai MS 852, once belonging to Crowland Abbey. Of note for genealogical interest is one in particular, Gesta Antecessorum Comitis Waldevi, while presents a curious pedigree that appears to have been largely derived from a similar account in John of Worcester's work, that tells of a polar bear via a woman of good birth [produced a son] Spratlingus, who had Ulsius, Ulsius having Beorn, [called Boresune, that is son of a] Bear, and Beorn having Siwardus, i.e. Siward, father of Waltheof. The manuscript is damaged, plus this portion is written in a different hand over an erasure so it was not pristine to begin with, but there follows another, Vita et Passio Venerabilis Viri Gualdeui, Comitis Huntendoniae et Norhantoniae, that summarizes the same account and allows the unreadable material to be deduced (in brackets above).
As Bolton points out, this pedigree is found in two other places. It has clear affinity to the pedigree of provided by John of Worcester in reporting the invasion by king Harold's brother, Sweyn Godwinson: Jarl Bjorn, his uncle's son, son of Danish Jarl Ulf, son of Spracling, son of Urse, and he (Beorn) is brother of Danish king Svein [Estrithson]. The similarities of these pedigrees has long been recognized. With the forms Ulsius for Ulfius and Spratlingus for Spraclingus both being clear copying mistakes, the two are effectively identical, with the Gesta simply making Siward the son of Jarl Bjorn, and giving a more elaborate tale about the origin of Spraclingus. Likewise we see something similar in Saxo Grammaticus' Gesta Danorum: an enormous bear absconds with a Swedish maiden and rather than eating her he ravishes her, and she gives birth to a son named for his father (i.e. Bjorn/Urse), who in turn had Thrugillus, called Sprageleg, to whom Ulf was born. These clearly represent a single genealogical tradition in which the father of Jarl Ulf, commonly called Thorgils Sprakalagg, had ursine heritage.
But it can't be true. The likely marriage date of Jarl Ulf to Estrid Knutsdottor is way too recent for them to be grandparents of Earl Siward. However, Bolton points to a critical inconsistency in the Gesta Antecessorum - it refers to Siward's father as Bearson, even though it was his supposed grandfather Spratlingus or great-grandfather who actually had a white furry father. This could, I suppose, be explained if the family used the bear as a totem, such that each consecutive generation would be son of a 'bear', a possibility Bolton doesn't consider. Instead he turns to another source, which is of late date, perhaps as late s the early 15th century, but that appears to preserve an earlier form of the tradition of Siward's parentage than found in the Gesta Antecessorum. This is the misnamed Chronicle of John of Brompton (he being the later owner of a copy, not its author). It reports what is clearly the same story, except that the genealogy is much shorter - the brute has a son Earl Bern, father of Siward.
Bolton suggests that this represents the earliest form of the legend with regard to Siward's ancestry, and that the second hand of the Gesta Antecessorum has 'corrected' this based on the pedigree of Jarl Bjorn in John of Worcestor, not realizing that they were different men, sharing the same tradition because one was great-uncle of the other. In short, he would suggest that Siward and Ulf were first cousins, (which would of course also make Siward relative of the Godwinsons. He would suggest that rather than the unlikely coincidence of two independent families latching onto the same ancient Norwegian legend that they represent branches of the same family, who when they rose to prominence in the late 10th/early 11th century, would convert their grandfather Bjorn (bear in the Scandinavian languages) into a actual bear.
Of course, being descended from a bear is OK for an ancestor in the remote past, but kings really need to descend from other kings in the male line, and then from gods, so at some later point the cursed ursid was reversed back into a man, Bjorn, only not just any Bjorn - Styrbjorn, leader of the Jomsvikings, son of King Olaf of Sweden, and with the Norwegian sagas marrying Styrbjorn to the daughter of Gorm the Old, supplying further validation of the family's right to succeed to the crown.
My question - what is the first source that makes this claim, that Thorgils Sprakalagg was son of Styrbjorn, rather than just Bjorn/Urse/Ursus maritimus? It clearly post-dates John of Worcester and Saxo Grammaticus, but when is the first it appears?
Manuscripts - I have been providing online links to digital images where I can find them, but this is not a good day for that. I am pretty sure the Douai ms is not online. Their web page announces with pride that the process of cataloguing! their material electronically is underway, which puts them about 30 years behind the whole digital learning curve, so we can expect images to go online about 2040. There are two exemplars of the Brompton (sic) Chronicle:
CCCC 96
https://parker.stanford.edu/parker/actions/page_turner.do?ms_no=96 (see f. 90r)
and
BL Cotton MS Tiberius C xiii (not online)
As to Saxo, only fragments survive. There was a complete manuscript found in the early 16th century that was used for a printed edition, but the original seems since to have been lost.
taf