Erle Melvin Koshak was one of the organizers, with Mark Reinsberg and Bob Tucker, of Chicon I, the second World Science Fiction Convention, held at the Hotel Chicagoan, September 1-2, 1940. He was secretary of the concomm and presided over the first day of the con as "temporary chairman", when Reinsberg, the official chairman, fell ill. The earliest lists of Worldcons (though not Chicon's own!) named him as the chairman, though Reinsberg was restored to that position in the list published by Discon II in 1974.
After World War II, Korshak established a used book business, which led in 1947 to Shasta Publishers, one of the first hardback SF speciality presses. The company's first major book was The Checklist of Fantastic Literature by Everett F. Bleiler (1948), a pioneering work of SF bibliography. This was followed by major works by Heinlein, Bester, Fredric Brown and others. Unhappily, overambitious expansion and an ill-fated effort to diversify into mainstream publishing brought the venture to an end in 1957. The verdict of Jack Chalker and Mark Owings in The Science Fantasy Publishers was that Shasta and Korshak "had more lasting impact than many major specialty presses of today ever will or could".
Korshak did not have much contact with fandom for the next 30 years. After graduating from law school, he became successful as a lawyer and businessman in California and Nevada. Starting in the late 1980's, he began attending conventions again. With his son, Stephen D. Korshak, he revived the Shasta imprint (as "Shasta/Phoenix") in 2009 to publish collections of classic SF art.
He was inducted into the First Fandom Hall of Fame in 1996, and won the Barry R. Levin Science Fiction and Fantasy Literature Lifetime Collectors Award in 2001.