Carl Farness travels to 300-372 and learns that he must betray his followers whereas Nicholas van Rijn travels to Mirkheim where he learns that he has been betrayed by David Falkayn. We see both Carl and van Rijn at their most vulnerable - which is unusual for van Rijn.
Are these comparisons fanciful? Yes. However, the point is that Poul Anderson wrote powerful stories about authentic characters in diverse and exotic spatiotemporal settings.
Another example: Daven Laure travels to the Cloud Universe where he learns that it will be impossible for him to marry the woman that he loves.