The book was so explosive it was banned is some counties in Calif. Particularly, Kern County.
From a history on the banning:
The resolution to ban The Grapes of Wrath and discourage the movie from being made was brought to the board by Stanley Abel, supervisor of the 5th district.... The vote - taken with no consultation of librarian Gertrude Knief and no advanced publicity or discussion - was 4 to 1 in favor of the ban.
They were embarrassed by how the book pointed out how the locals treated the desperate Okies. And found that the cost of city services was causing - TAXES to go up. And you know how Republicans hate taxes!!! One of those expenses - libraries.
In the controversy that followed the ban, it became clear that Stanley Abel had acted on behalf of the Associated Farmers and other powerful political forces in Kern County. ... Earlier in Stanley Abels political career, his connection to the Ku Klux Klan had been exposed, but in spite of a Grand Jury probe, he took pride in being a member and said, I make no apology for the Klan. It needs none. But Stanley Abel wasnt merely another racist redneck; by virtue of his long tenure on the board, he was part of the conservative Republican political power structure of Kern County.
Anyone surprised?
Steinbeck meant his book to be searing:
"It is a mean, nasty book, and if I could make it nastier, I would. ...I am not writing a satisfying story. I've done my damndest to rip a reader's nerves to rags. I don't want him satisfied." - John Steinbeck to his agent, Elizabeth Otis, who wanted to change the breast-feeding ending to "The Grapes of Wrath," 1939.