Wikerus, a young German noble joins the Teutonic Order of knights and fights in the Fifth Crusade. He meets the Swan Knight, the sworn protector of the Holy Grail, and becomes his steward. After the crusade, Wikerus lives in a secluded Bavarian valley with the Swan Knight’s family. He finds love and fear, bliss and more war. He escapes his previous life and roams the Holy Roman Empire as a philosopher, poet, and minnesänger, giving birth to the legend of the Tannhäuser.
I found The Tanhauser to be an interesting story.