Harry Backer Warner Jr. was an American journalist who spent 40 years working for the Hagerstown, Maryland, Herald-Mail. He was also an important science fiction fan and historian of fandom and Washington County, Maryland, as well as a classical musician.
Warner was born in 1922 in Chambersburg, Pennsylvania. Due to poor health, he dropped out of Hagerstown High School by the 10th grade. Despite his lack of formal education, he was a well-read and learned man, an autodidact who taught himself seven languages. During World War II, he translated letters from overseas to families of American soldiers. Warner never married. On his death, he left most of his possessions to a Hagerstown Lutheran church.
Early in the book, Warner apologizes for his history being a narrative, and not analytical. But it's never really a narrative.
Not unlike his (much) earlier "All Our Yesterdays," Warner's history of science fiction fandom in the 1950s is fragmentary. There are sections on fandom in various places--cities, regions, non-U.S. countries, as he sees fit to divide them--or a certain times or on certain themes or particular people.
Probably it would be most interesting to people who actually lived through the times. As it is now, it is mostly useful as a reference to consult, and not something to read through--and even at that, it is becoming somewhat dated. Warner says (again toward the front of the book) that very few people have access to all the materials he used to write the book. Which is true! But less so than when he wrote it.
Increasing numbers of old 'zines are being put onto the web, and so the raw material, the various stories that Warner recounts--these can be gotten by even people who were not collecting he material int he 1950s. Now, there's still a wealth (ahem!) of material that remains impossible to get, and Warner could also work from his own memories.
But the wide(r) availability of the professional and amateur magazines from the middle of the 20th century means that what is wanted is a book that makes sense of the raw material, and doesn't just present it.
There is a thesis here, but it's very loose. The inmates have taken over the asylum.
In the quarter century before 1950, science fiction fandom was an asylum in the sense of it being a safe place for people who loved science fiction, often in ways not understood by the creators of the things that they loved: the writers, artists, and editors. There was a push-and-pull.
By 1950, science fiction was entering the mainstream, where it was buffered somewhat from the fans; and, as importantly, many of the earlier fans were now in control of producing science fiction--not just stories and magazines, but movies and TV, too--they were in control of the asylum--which made the push-and-pull much more personal even as the professionalization of science fiction meant that fans were increasingly adrift, their subculture dropping the "sub" to become its own thing.