NEW YORK, NY.- In the 50 years since it came out, “The Chocolate War” has become one of the country’s most challenged books. But the tensest battle over the novel may have been fought in Panama City, Florida, in the mid-1980s. That’s when an attempt to ban “The Chocolate War” divided the town, leading to arson and death threats against middle-school teachers.

Early in 1986, English teachers at Mowat Middle School protested a schoolwide ban against a select number of novels, including Robert Cormier’s “The Chocolate War.” The book, published in 1974, had been long been criticized by some parents for its modest locker-room talk and anti-authority worldview — and enjoyed by the young in part for the same reasons.

The Mowat teachers endured all sorts of harassment because of their stand. Pranksters called in the middle of the night, calling them lesbians and witches. Parents harangued them at community meetings. Even some of their colleagues turned against them.

That fall, a sloppily addressed letter was found at the Mowat offices. It featured the words “YOU ALL SHALL DIE” in letters cut out from magazines, and mentioned several teachers by name — including Alyne Farrell.

“That was when the you-know-what really hit the fan,” said Farrell, now 76. “I was a single woman with a young child, and I lived alone. We had police sitting in our driveway for three days and nights.”

Yet the teachers had a notable ally: Cormier himself.

Not long after the “YOU ALL SHALL DIE” message arrived in the mail, another letter made its way to Mowat. This one was part apology, part lament.

“I have been at a loss for words,” Cormier admitted in his note. “The ironic thing is that words are my business, and the words I used in my books have been the cause of so much trouble.”

Cormier died in 2000 at age 75. A trove of his letters and essays at Fitchburg State University provide a glimpse at how an author’s life is affected when a book unexpectedly inflames a long-running war. Many writers are having a similar experience today, with books facing opposition at libraries and schools nationwide — including, once again, in Panama City.

As Cormier would remark to one of his children, “I’m weary of the battle, but a tired fighter can still be a fighter.”

For a book that proved to be so provocative, “The Chocolate War” had an innocuous enough birthplace: the Cormier family dining table in Leominster, Massachusetts. During dinner one night in the fall of 1968, Cormier’s son, Pete, told his father he’d been tasked with selling chocolates as part of a fundraiser for his private school.

The elder Cormier, who was no fan of authority, told his son he had his permission not to participate — he didn’t have to go along with the crowd.

“He was encouraging me to take a stand,” Pete Cormier said in a recent video interview. “I was a skinny freshman — a low man on the totem pole — and this made me feel like a rebel.’”

Over the next few years, while working as a newspaper editor and columnist, Robert Cormier stayed up late at night, spinning Pete’s minor act of defiance into “The Chocolate War.” The book follows a small-town freshman named Jerry Renault, whose refusal to sell candy for his school earns him the ire of a manipulative headmaster and the vengeance of an underground student group known as the Vigils. By the book’s end, Jerry has been harassed, beaten and ostracized, leaving him just as alone as ever.

“The Chocolate War” wasn’t an easy sell: Several editors rejected the book, citing its violence, language and pessimistic message. But teens in the 1970s were eager for stories that reflected their angst and anxieties, and novels like S.E. Hinton’s “The Outsiders” and Judy Blume’s “Are You There God? It’s Me, Margaret” had become hand-me-down hits.

The relatably bummed-out tone of “The Chocolate War” — paired with Cormier’s economical prose and hyper-specific recall of adolescent cruelty — was aimed at young readers who’d become skeptical of the grown-ups running their world.

“You don’t have to go to a Catholic boys’ high school to realize that the school system is inherently screwed up and manipulative,” said actor and filmmaker Keith Gordon, who wrote and directed a 1988 adaptation of Cormier’s book.

After its release in 1974, the book went on to become one of the most celebrated young adult novels in the country — and one of the most hotly contested.

It spurred book-ban attempts in towns like Proctor, Vermont (where the novel was assailed for its “negativism”); Columbia, South Carolina (for “pervasive vulgarity”); and Groton, Massachusetts (for “less than wholesome sexual activity).”

Cormier spent hours responding to the various book-ban squabbles — a job he resented at times. “I am furious, because I would rather be working on my novel,” he wrote in a draft for an essay. “Or even looking out the window, thinking about my novel.”

In many cases, the book was eventually reinstated, though in some cases, students still needed special permission to get a copy. “Even when you win, you lose,” Cormier wrote.

By the late 1980s, a conservative political wave was sweeping the country, and opposition to “The Chocolate War” — as well as some of Cormier’s subsequent books — increased. According to a 1987 report by the People for the American Way, “The Chocolate War” was by then the most-challenged book in the United States, ahead of “The Catcher in the Rye” and “Of Mice and Men.”

“The fundamentalists are certainly rolling in high gear,” Cormier wrote in 1987, “and it gives me the chills.”

He responded by inviting educators to his Massachusetts home, granting numerous interviews and corresponding with supporters and critics alike. He was anguished when he heard from teachers whose jobs were on the line because they wanted to use “The Chocolate War.” He wondered if he should encourage them: “Do I have the right to ask others to risk themselves,” he wrote, “while I remain safe?”

The Mowat Middle School fight troubled him.

“The attacks have accelerated,” Cormier told the Mowat teachers. “I feel very guilty these days as I sit at my typewriter … other people are fighting my battles.”

Such battles would continue well into the 1990s and 2000s, making “The Chocolate War” one of the few young adult novels to aggravate grown-ups across multiple generations. As of January, it was still on at least one banned book list in Florida.

For all the book-ban skirmishes Cormier waded into, nothing had prepared him for the ordeal in Panama City.

The fight had been ignited not by “The Chocolate War,” but by another Cormier novel: “I Am the Cheese,” his 1977 thriller about a troubled young man who can’t remember his past. When the parent of a Mowat seventh-grader objected to the book — citing its language and “morbid and depressing” tone — school officials immediately yanked it from classes, along with a few other titles, including “The Chocolate War” and Susan Beth Pfeffer’s “About David,” a 1980 novel about teen suicide.

For Farrell, whose ninth-grade English curriculum at Mowat included “I Am the Cheese,” the decision felt like a step backward. She and several other teachers had spent years revamping the school’s English department, getting rid of decades-old grammar textbooks and looking for provocative new stories that would get their students interested in reading. Cormier’s novels were a perfect fit.

The Mowat teachers pushed back on the ban, prompting an angry backlash. A grandparent with connections to Mowat was so offended by “The Chocolate War” that he took out an ad in a local paper, highlighting snippets of the book’s dialogue that included words like “bastard” and “goddamn.”

“Your child’s TEXTBOOKS,” the ad read. “HAVE YOU READ THEM?”

“Once they lit into poor old Robert Cormier,” Farrell said, “he didn’t stand a chance.”

Public meetings grew tense, and according to one account from the time, a school superintendent barged into the English department’s workroom and scolded the teachers for championing “depressing” books. Predictably, the controversy made the book a bestseller in local stores.

Then things turned scary: After a local TV reporter revealed that a petition supporting the ban contained invalid signatures, she woke up to the smell of smoke and found that a flammable liquid had been set ablaze under her apartment door.

“When I see the situation at Mowat, I can only shudder,” Cormier wrote in a letter to the teachers. “I remember being in precarious situations as a reporter, but never with death threats and arson.”

Book banning in Panama City continued, eventually growing to include such classics as “The Great Gatsby” and “Twelfth Night.” It wasn’t until a group of students — led by Farrell’s 13-year-old daughter, Jennifer — filed a federal class-action lawsuit in 1987, claiming their constitutional rights had been violated, that officials slowly began returning titles back to classrooms.

Eventually, Cormier made his way to Panama City and met with the Mowat teachers.

“He wanted us to know that he was pleased,” Farrell said. “He was giving us all the credit.”

By then, the dust-up in Panama City was quieting down. But, as with so many book-ban fights, no one walked away from the battle feeling triumphant.

“There was no big victory,” Jennifer Farrell, now 50, said. “Everyone lost. It was a time when the excitement of fighting against oppression should have been uplifting, and it wasn’t at all. In the end, it made the entire community suffer.”

Still, for all his regrets about the trouble “The Chocolate War” had caused for others, Cormier continued to defend it staunchly in the last years of his life.

“The message of ‘The Chocolate War,’” he noted, “is that evil succeeds when good people allow it.”

This article originally appeared in The New York Times.