Sam Moskowitz
Sam Moskowitz (1920-1997) was an early fan and organizer of interest in science fiction and, later, a writer, critic, and historian of the field.
As a teenager, he organized a branch of the Science Fiction League. Meanwhile, Donald A. Wollheim helped organize the Futurians, a rival club with Marxist sympathies. Moskowitz became chairman of the first World Science Fiction Convention held in New York City in 1939. He barred several Futurians from the convention because they threatened to disrupt it. This event is referred to by historians of fandom as the Great Exclusion Act.
books featuring Sam Moskowitz