Mary Shelley’s Frankenstein (1818) is said to be one of the earliest ‘proper’ works of science fiction, but the pulp magazine established it in the USA and was one of the most influential publications for the genre.
Hugo Gernsback published AMAZING STORIES in 1926 and put the genre on a fine trajectory.
Take a read of the first issue and many more courtesy of the Internet Archive.
We love digging around this site, and we are sure you will too. Films, magazines and so much more are all here for free!