‘New wave‘ SF came out of the UK and birthed a multitude of sub genres we see today, cyberpunk, steampunk etc. It had its peak in the late 60’s and was established by Michael Moorecock. He disliked the John Campbell pulp of the genre and legitimised SF and Fantasy into a literary form.
Roger_Zelazny was one of the first of the ‘new wave’ SF Writers whose ‘This Immortal’ book came second to Dune at the Hugo awards in 66. At the time it was considered cutting edge. It hasn’t aged well but is a very good example of the ‘new wave’ writers and also the beginning of myth being employed in modern sf.
This is a good review of the plot from tor books:
This is another good review from a journal this goes into the mythological background of the novel:
This Immortal | Open Library
Open Library is an initiative of the Internet Archive, a 501(c)(3) non-profit, building a digital library of Internet sites and other cultural artifacts in digital form.Other projects include the Wayback Machine, archive.org and archive-it.org