This note contains spoilers for the book.

An old "Garland Library of Science Fiction" volume (paperback size hardcover, no dust jacket, gray speckly cloth covers). Appears to be a facsimile of the 1963 Ace Books edition (a $0.40 paperback).

I'm sure jumping around in the timeline here! Well, starting with Empire I guess I couldn't have done anything else.

We're on one of the Sword Worlds, while they're busy plundering the old Federation. They've been doing it long enough that they're starting to go decadent themselves—for one thing all the good genetic stock is leaving to raid and make their fortunes.

We start with a baron marrying his dream wife, and both getting killed immediately after by the crazy local suitor. The killer steals a ship (incidentally nearly bankrupting the Duchy) and runs off. Baron Trask is determined to follow and get his revenge.

And he heads off to do so, giving up his barony to finance it. And in the process ends up turning Tanith into a civilized planet, and at least somewhat delaying the fall of civilization in that part of the galaxy. He comes to not care much at all about his revenge. And, if the history in the short stories is to be believed, he made no difference at all in the long run.