On the Road Author Jack Kerouac’s Success ‘Accelerated’ His Drinking (Exclusive)

Jack Kerouac’s ex-girlfriend is recalling how the success of his breakthrough 1957 novel On the Road negatively affected the legendary author.

Joyce Johnson, a New York City-based author who dated Kerouac for roughly two years around the time of On the Road’s publication, recently sat down with filmmaker Ebs Burnough and PEOPLE to discuss Burnough’s new documentary Kerouac’s Road: The Beat of a Nation, which revisits Kerouac’s life and work some six decades after the book was initially published and made Kerouac one of the public leaders of the “Beat Generation.”

Johnson was with Kerouac, who died in 1969 at age 47, as he read the first review of his novel in The New York Times. She tells PEOPLE Kerouac wasn’t prepared for the attention the book received.

“We knew there was going to be a review, and the review immediately kind of pointed to Jack as a spokesman of an entire generation. I don’t think being a spokesman was his thing,” Johnson says. “In some ways he was a deeply shy person.”

Kerouac’s Road explores Kerouac’s upbringing in Lowell, Mass., in a French-Canadian family, as well as the impact of On the Road’s themes on modern-day Americans. As Johnson notes, Kerouac spoke French as his first language; she feels he held “an outsider’s view of America,” despite becoming one of the country’s most popular 20th-century authors.

“He’d been a kid who never spoke in class. It was a terrible strain for him. And suddenly he was in demand. Everybody wanted interviews,” Johnson says of the public’s reaction to On the Road, which follows two main characters — based heavily on Kerouac himself and Beat Generation figure Neal Cassady — on a series of cross-country road trips in the late 1940s and early 1950s.

“He was on early TV talk shows, which was a very unusual experience for a writer back then. And in order to go through with all these public appearances, he would have to drink a lot,” Johnson recalls. “He drank anyway, but the drinking really accelerated terribly. And then he was under a tremendous attack all the time. All the publicity — some people were very enthusiastic about the book, and other people thought the Beat Generation would bring waves of juvenile delinquency.”

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“The literary establishment turned up their noses at On The Road and attacked his writing, so it became a very painful experience for him,” she adds. “And it kind of it kind of destroyed him, actually. He also lost his anonymity, which was a very valuable thing. If you’re going on the road, nobody knows who you are.”

Oscar-nominated actors Matt Dillon and Josh Brolin sat for interviews for the new documentary, as did comedian and television host W. Kamau Bell, singer-songwriter Natalie Merchant (whose former band, 10,000 Maniacs recorded a song called “Hey Jack Kerouac” for their 1987 album In My Tribe), scholar Ann Charters, composer David Amram and Bright Lights, Big City novelist Jay McInerney. 

Kerouac’s Road: The Beat of a Nation is in theaters now.