This is an almost legendary meeting. We know Lord Bear from the previous volume and some of us know a version of Sir Nigel from a historical novel. See image.
In Poul Anderson's works:
Beowulf crosses over with Hrolf Kraki (see here);
Macbeth is mentioned in a novel about Harald Hardrada (see here);
Macbeth and Hamlet are mentioned in Anderson's Shaespearean novel (see here).
And I did not expect the meeting between Sir Nigel and Lord Bear to recall those more illustrious cross-references.