Hugo Gernsback had such a huge impact on the history of science fiction that one of the field's most prestigious awards is named after him. But after he founded Amazing Stories in the 1920s, the pioneering editor had a long slide into obscurity. The National Post has a great article about the life and influence of Gernsback, on the 90th anniversary of his founding of Amazing Stories. The most interesting bit, though, comes at the end, when they talk about how Gernsback became "an eccentric fading force" in the 1930s. By the early 1950s, his main impact was that fans started a fight about him at a convention that sent a few people to the hospital. He tried to publish another science fiction novel around that time, after his groundbreaking Ralph 124C41+, but nobody wanted to publish it. He also approached Isaac Asimov about starting a new magazine in the '50s, but Asimov turned him down.
The whole thing leads up to a sad finale -- the decade following Gernsback's death in 1967 saw him reevaluated by science fiction experts, and accused of everything from murdering science fiction to being one of science fiction's worst disasters. But he still gets shiny rockets named after him every year, at least. [National Post]
Top: A cover of Electrical Experimenter, one of Gernsback's early magazines