By the summer of 1965, there were signs that Bob Dylan had entered a new phase of his career. The wild-haired troubadour had traded his everyman garb for sunglasses, trendy suit jackets and pointy-toed boots, and he was beginning to distance himself from his reputation as a protest singer and folk balladeer.

Just five days before the Newport Folk Festival, he released “Like a Rolling Stone,” a six-minute-long single that combined stream-of-consciousness lyrics with electric guitar and catchy organ riffs. The tune was already in circulation on the radio, but Dylan had yet to perform it with a live band. As far as the diehard folkies gathered at Newport were concerned, he was still a solo acoustic act.

Dylan’s first appearance at the 1965 festival came on Saturday, July 24, when he performed with his usual acoustic guitar and harmonica at a Newport songwriter’s workshop. Both the crowd and the festival’s organizers assumed he would play a similar show at the event’s star-studded Sunday night concert, but Dylan—seemingly on a whim—had decided it was time for something new. After leaving the stage on Saturday, he assembled keyboardist Al Kooper and members of the Paul Butterfield Blues Band and stayed up until dawn rehearsing for an electric rock ’n’ roll show.

Dylan’s new amplified sound made its live debut the following night. After being introduced by Peter Yarrow of Peter, Paul and Mary, the 24-year-old strode onto the stage carrying a Fender Stratocaster guitar and wearing a leather jacket. As a confused audience of 17,000 fans looked on, he and his band roared to life with a manic rendition of the song “Maggie’s Farm” off his recent album “Bringing it All Back Home.” Guitarist Mike Bloomfield took the lead with a jarring electric guitar riff, while Dylan leaned into the microphone and shrieked the opening lyrics, “I ain’t gonna work on Maggie’s farm no more!”

The song’s aggressive tempo and Bloomfield’s distortion-laden guitar hit the audience like a shockwave. Some cheered, but a significant portion began booing, and the outrage only grew after the band transitioned into “Like a Rolling Stone.”

This wasn’t the Dylan the folk purists in audience had paid to see. To them, it was a musical betrayal—proof that he had abandoned the authenticity of folk for the glitz and glamor of rock ’n’ roll. As the set continued, portions of the crowd erupted with jeers and scattered cries of “sellout!” and “get rid of that band!” The scene was even more frantic backstage. Rumors would spread that festival organizer and folk legend Pete Seeger was so dismayed that he grabbed an axe and tried to wreck the sound system. The tale is little more than a myth, though Seeger later said that he did fume, “If I had an axe, I’d cut the cable right now!”

Just how hostile the response really was—and why—has since become a matter of considerable debate. Many witnesses, Seeger included, maintained that the booing was due more to the poor sound quality than the shock of seeing Bob Dylan picking away at a Stratocaster. The audio mix at the outdoor venue was far from ideal, and Bloomfield’s guitar was turned up so loud that it drowned out Dylan’s lyrics. “I was furious that the sound was so distorted, you could not understand a word that he was singing,” Seeger later said.

Others were no doubt miffed about the set’s short length. The night’s schedule was already crammed with artists, and Dylan and his band had only managed to rehearse a few songs. After finishing “Like a Rolling Stone” and plodding through a third tune, they abruptly unplugged their instruments and left to muted applause and a fresh chorus of boos. In a desperate effort to calm the raging crowd, Yarrow pleaded for Dylan to grab his acoustic guitar for a brief encore. Dylan reportedly wasn’t happy about the request, but he returned and played solo versions of “It’s All Over Now, Baby Blue” and “Mr. Tambourine Man” before finally leaving the stage for good.

Dylan’s entire set had consisted of just five songs—and only three of them electric—yet it was seen as having massive implications for his future as an artist. In the days that followed, music journalists debated whether he was selling out his audience for a chance at pop stardom, and many criticized the electric gig as a shameless attempt to appeal to the youth culture. “Dylan now sings rock ’n’ roll, the words mattering less than the beat,” wrote the Providence Journal. “What he used to stand for, whether one agreed with it or not, was much clearer than what he stands for now. Perhaps himself.” Likewise, many of Dylan’s fellow folk musicians considered the blaring electric tones contrary to the spirit of Newport. “You don’t whistle in church,” singer Theodore Bikel told a reporter, “you don’t play rock ’n’ roll at a folk festival.”

The controversy would continue to haunt Dylan when he went on tour a month later. His shows—which included both electric and acoustic sets—were often met with boos and pleas for the return of the “old Dylan.” One man even screamed “Judas!” at him during a concert in England. There was no denying the quality of the material, however, and it wasn’t long before most of the audience got onboard. Dylan’s next rock album, “Highway 61 Revisited,” was hailed as an instant classic, and “Like a Rolling Stone” became his first hit single. By the time his album “Blonde on Blonde” was released in 1966, many former critics were forced to admit that electric instruments had not dampened his flair for writing rebellious songs or poetic, quotable lyrics.

The Newport Folk Festival wouldn’t be the last time that Bob Dylan reinvented himself, but it is now remembered as a pivotal juncture in his career. It was the moment when he proclaimed his artistic independence and helped usher in a new era of lyrics-driven rock ’n’ roll. That didn’t mean he wasn’t affected by the criticism he received from the folk community. Dylan had never planned on causing a rift by picking up the electric guitar, and the booing he received during his 1965 set reportedly left him shaken. While he later returned to his acoustic roots on subsequent records, he wouldn’t appear at Newport again for another 37 years.