WHEN BOB DYLAN returned to the Newport Folk Festival three weeks ago, the 61-year-old icon didn't stand a chance of eclipsing his prior performance at that fabled event on July 25, 1965. That's when a 24-year-old Dylan enraged folk purists by playing three songs with an electric band that included guitarist Mike Bloomfield and keyboardist Al Kooper, and the mythos surrounding that brief plugged-in set has only grown over the decades. Many consider it the defining moment for folk and rock in the 1960s, necessitating the first genre-melding hyphen and making it impossible to turn back from the advent of folk-rock.

I don't remember it quite that way. I was a 15-year-old suburban California kid at the time, and Newport was as distant culturally as it was geographically. I was just beginning to listen to Dylan's records, having come to him by way of a fairly typical white-bread diet of Peter, Paul, and Mary and Ian and Sylvia. I don't recall reading about Dylan's Newport heresy in 1965, and if I did, it probably seemed irrelevant in light of his electric rock-oriented tracks on Bringing It All Back Home (released the previous March) and the Byrds' hit version of "Mr. Tambourine Man" (number one that June). Folk-rock was a fait accompli, a seemingly natural phenomenon that within a year gave us everything from We Five's "You Were on My Mind" to Dylan's Highway 61 Revisited and Blonde on Blonde, the Beatles' Rubber Soul, and the Byrds' "Eight Miles High."

In the prologue to his new book, Turn! Turn! Turn!: The '60s Folk-Rock Revolution (Backbeat Books, $19.95), Richie Unterberger devotes 20 pages to "The Great Folk-Rock Clash," as he calls the 1965 Newport controversy. But the rest of his deeply researched, 300-page paperback basically confirms my teenage intuitive grasp of the musical evolution I was hearing. "Dylan's electric rock debut at Newport did not change the world," Unterberger writes, "so much as announce that the world had changed."

That revelation may have shocked those in attendance at Newport for whom acoustic instruments and a dogmatic notion of authenticity formed a folk music holy grail, or those who couldn't let go of the "Blowin' in the Wind"/"Masters of War"/"The Times They Are A-Changin' " Dylan they'd installed at the vanguard of politically conscious contemporary folk. But for those of us who didn't have any direct pipeline to, or much ideological investment in, the folk scene per se and who got our pre-Rolling Stone music news not from Sing Out! magazine but from radio and television, Dylan's "going electric" didn't seem like such a big deal. As Arlo Guthrie told Unterberger, "Popular music in those days wasn't really separated for marketing purposes like it is today. On one radio station, you could hear the Kingston Trio and the next minute you could hear the Everly Brothers, as well as Perry Como or somebody else." In 1965, Petula Clark, the Righteous Brothers, Tom Jones, the Temptations, Roger Miller, the Stones, and the Beatles all had top-five hits.

Moreover, given how fast both Dylan and pop music were changing between 1963 and 1966 – with the Beatles taking the United States by storm in 1964 – focusing on a specific turning point for plugged-in folk almost seems beside the point. One of the strengths of Unterberger's fact-laden study is the way the dense accounting of recording sessions, record-label politics, musical cross-fertilization, and debates over purity and selling out builds into a swirl of cause and effect that transcends linearity. Obsessive about musical minutiae, Unterberger creates kaleidoscopes of details and cacophonies of voices (from more than 100 musicians, producers, managers, and journalists) that feel more representative of the period than any one event or song ever could.