A number of trees have given Øystein two wifes named "Ascrida" and "Jocunda". Very odd names for a Viking noble's wives.
In hunting around for where this story comes from (a much more useful mission, in my mind, than verifying whether this story is "true"), I've come across this reference:
Title The American historical magazine, Volume 3
Authors Publishing Society of New York, Americana Society, Americana Society (New York, N.Y.)
Publisher The Publishing Society of New York, 1908
where Google Books gives me this snippet:
"BOOK OF BRUCE
EYSTEIN, or EUSLIN, named Glumra of Vors, son of the preceeding, fled into the kingdom of Norway about 870 to escape Dansih tyranny. He married, first Jocunda, daughter of Hunt-
End of snippet. The search function claims that the word "Ascrida" occurs on the same page. It's likely that some of the people here may be able to read more, or even point to what the "Book of Bruce" is and where it's available to a Norwegian.
Help?