On May 12, 1963, the young and unknown Bob Dylan walked off the set of "The Ed Sullivan Show," the country’s highest-rated variety TV show, after network censors rejected the song he planned on performing.

By the end of that summer, Bob Dylan would be known to millions who watched or witnessed his performances at the March on Washington, and millions more who did not know Dylan himself would know and love his music thanks to Peter, Paul and Mary’s smash-hit cover version of “Blowin’ In The Wind.” But back in May, Dylan was still just another aspiring musician with a passionate niche following but no national profile whatsoever. His second album, The Freewheelin’ Bob Dylan, had not yet been released, but he had secured what would surely be his big break with an invitation to perform on "The Ed Sullivan Show." That appearance never happened.

The song that caused the flap was “Talkin’ John Birch Paranoid Blues,” a satirical talking-blues number skewering the ultra-conservative John Birch Society and its tendency to see covert members of an international Communist conspiracy behind every tree. Dylan had auditioned “John Birch” days earlier and had run through it for Ed Sullivan himself without any concern being raised. But during dress rehearsal on the day of the show, an executive from the CBS Standards and Practices department informed the show’s producers that they could not allow Dylan to go forward singing “John Birch.” While many of the song’s lyrics about hunting down “reds” were merely humorous—”Looked up my chimney hole/Looked down deep inside my toilet bowl/They got away!“—others raised the fear of a defamation lawsuit in the minds of CBS’s lawyers. Rather than choose a new number to perform or change his song’s lyrics, Dylan stormed off the set in angry protest.

Or so goes the legend that helped establish Dylan’s public reputation as an artist of uncompromising integrity. In reality, Bob Dylan was polite and respectful in declining to accede to the network’s wishes. “I explained the situation to Bob and asked him if he wanted to do something else,” recalls "Ed Sullivan Show" producer Bob Precht, “and Bob, quite appropriately, said ‘No, this is what I want to do. If I can’t play my song, I’d rather not appear on the show.'” It hardly mattered whether Dylan’s alleged tantrum was fact or reality. The story got widespread media attention in the days that followed, causing Ed Sullivan himself to denounce the network’s decision in published interviews. In the end, however, the free publicity Bob Dylan received may have done more for his career than his abortive national-television appearance scheduled for this day in 1963 ever could have.