Poul Anderson may be the greatest, unknown-outside-of-SF-nal circles author. Why he (and his vivid, poetic prose, and his complex characters) is steadfastly ignored, while writers like Clarke and Asimov are hailed as the giants of the era, I do not know. I have my suspicions, which, in order, are that Anderson enjoyed writing plots full of heroic action, which lit-snobbery denounces as low, that Anderson wrote books full of joy and hope, which lit-snobbery denounces as false, and that Anderson was not sympathetic to Luddism or communism, both of which lit-snobs deem essential to real literature.
However, I stray from the point: One of the greatest post-apocalyptic books ever written is, in my opinion, Orion Shall Rise, which tells the story of people living in the successor states that have arisen after a great nuclear war. The Maurai, the most powerful of these states, embodied by its agent, Terai Wanaroa, are determined to thwart any move toward rebuilding any technology that they deem a threat to the planet, while the Northwest Union, their rival, is embarking on a course that could return the stars to mankind, while also reviving its most dreadful weapons.
The future history is plausible, the characters are beautifully-flawed humans, and the story is heartbreaking with loss and hope. I fully recommend it to everyone, except possibly those who really can’t stand any hint of sexism, because frankly, there is some there, it’s not perfect. But that having been acknowledged, I strongly recommend it as a brilliant and sadly forgotten story.