Murray Constantine (Katharine Burdekin) Swastika Night (1937).
Good Reads meta-data is 208 pages rated 3.62 by 2909 litizens.
Genre: Dystopia.
DNA: Brit.
Verdict: Prescient and timely.
Tagline: ‘I told you so.’

Anno Domini 2444, five hundred years after Germany won World War II (yes the author saw that coming when even Charles Lindberg didn’t) together with the Japanese. Hitler has now been deified in gold. Women are herded like cattle and used only for selective breeding. Jews, homosexuals, the Bosox nation, Slavs, Romani, game shows hosts, Jehovah’s Witnesses, Quakers, and other subhumans have been exterminated. On the other side of the world the Empire of Japan luxuriates in its triumph by pillaging far and wide.
The demigod Hitler is portrayed as 7’ (2.1m) tall with a strong chin, blond hair, cobalt blue eyes, and dimples. Even better looking than Elvis.
No books are left to burn, but the thought police remain ever vigilant. If this is starting to sound like….
In the novel Hero begins to find out the truth about the war and Hitler and is hunted down by the aforementioned ICE agents and murdered. End of story. Downbeat indeed.

Irony is that in the free Britain of 1937 the author had to pose as a man to get her book published.
Further Reading: The Man in the High Castle (1962) by Philip K. Dick with its novel within a novel, which seems mild in comparison. Likewise, Swastika Night makes Handmaiden’s Tale seem like a fairy story.