Fury by Henry Kuttner

A little light reading for a change. This is set in the same Venus as "Clash by Night," where the refugees from a destroyed earth live in undersea domes because the land is too hostile. An Immortal (long lived mutant families) baby is modified and raised as an ordinary man--with an overwhelming urge to power.

Kuttner was a very creative and thoughtful writer, and he took a hard look at what kind of man a Barbarossa or an Arthur might be. Sam's early years aren't adequate to explain his nature, and Kuttner would have been better off just describing him and saying that some people are like that. When he leaves Sam's early history behind and goes on to tell what happens when Sam's ambition meets the last hope of the fading Keeps, the story works well.

Of course his Venus is all wrong, and the technology sometimes a little off, but these are trifling matters compared to the telling of a good story. And it is a good story, with some wonderful little asides, such as the Logician's explanation of why prophecies have to be obscure.