The following post by Curt Hofemann, curt_hofemann@@yahoo.com, indicates the difficulty in "proving" anything about these early Scandinavian peope. Their ancestry is taken mostly from 12th century writers and old Sagas passed down through the centuries. The sagas, which probably contain some "truths", also contain a lot of fabulous stories about the lives of the early rulers. As the people of the period did not have writing, it is difficult to "prove" anything.
On the other hand, after just a few years of medieval genealogy, I can probably name all of the kings of England, from memory, starting with Edward the Confessor, which is almost a thousand year period; and that is without any concerted effort to memorize them; I could probably go back further if I tried. There is no reason to assume that the people of the 12th century were any less inaccurate in their oral tradition of keeping track of such things as the ancestry of the Scandinavian ruling families.
Thus I don't believe in throwing such people on the trash heap because, by circumstance, they had nothing written about them by themselves or by their contemporaries. I think that such people should be included, but with an understanding that their information is, by necessity, obtained in a different and less precise manner than other people in one's family pedigree.
By that token, you can divide them into "historical" figures proven by something written during their lifetime or soon after, and "legendary" figures, who I think probably did exist, but are only proven by sagas and oral traditions written down in the 12th century.
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Earl of More [Ref: Wurts p421]
Jarl of Hademerken [Ref: Moriarty Plantagenet p170]
Eynstein the Eloquent, or Noisy [Ref: Watney #740]
Research note: Eysteinn Glumra (of dubious historicity). Genealogies in late Icelandic sources make Rognvaldr a son of Eysteinn Glumra, son of Õvarr, son of H·lfdan the Old [OI 1: 187 (from Landn·amabÛk iv.14.1); OS 3]. These sources are not independent, but depend on each other in a way that is not entirely clear. Given the general unreliability of the Scandinavian saga sources for such an early period, there is no good reason to believe that Eysteinn or the earlier generations are historical. [Ref: Henry Project citing:
OI = Gudbrand Vigfusson and F. York Powell, ed. & trans., Origines Islandicae, 2 vols. (Oxford, 1905).
OS = OrkS = Hermann P·lsson and Paul Edwards, ed. & trans., Orkneyinga Saga (London, 1978). Citation is by chapter, with the page number in parentheses]
Regards,
Curt