John Steinbeck banned the book from the county's publicly funded schools and libraries. It was burned in Salinas on two different occasions. In 2003, a school board in Mississippi banned it on the grounds of profanity. According to the American Library Association Steinbeck was one of the ten most frequently banned authors from 1990 to 2004, with "Of Mice and Men" ranking sixth out of 100 such books in the United States. The award of the 1962 Nobel Prize for Literature to Steinbeck was controversial in the United States. The award citation lauded Steinbeck "for his realistic and imaginative writings, combining as
John Steinbeck Wrath", in which themes of conversion and self-sacrifice play a major part in the characters Casy and Tom who achieve spiritual transcendence through conversion. Steinbeck's contacts with leftist authors, journalists, and labor union figures may have influenced his writing. He joined the League of American Writers, a Communist organization, in 1935. Steinbeck was mentored by radical writers Lincoln Steffens and his wife Ella Winter. Through Francis Whitaker, a member of the Communist Party USA's John Reed Club for writers, Steinbeck met with strike organizers from the Cannery and Agricultural Workers' Industrial Union. In 1939, he signed a letter with some