The book’s frame narrative and premise is that “after dabbling in radical politics,” Adolf Hitler emigrated to the United States in 1919 and became a science fiction illustrator, editor, and author. He wrote his final science fantasy novel Lord of the Swastika in six weeks in 1953, shortly before dying of a cerebral hemorrhage[1]: 245 perhaps caused by tertiary syphilis; Lord of the Swastika subsequently won the Hugo Award and the “colorful uniforms” described therein became staples of science fiction conventions.
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https://en.wikipedia.org/wiki/The_Iron_Dream