When Shirley Jackson’s story “The Lottery” was first published, in the June 26, 1948, issue of this magazine, Miriam Friend was a young mother living in Roselle, New Jersey, with her husband, a chemical engineer who worked on the Manhattan Project. An exact contemporary of Jackson’s—both women were born in 1916—she had recently left her job as a corporate librarian to care for her infant son, and she was a faithful reader of The New Yorker. “I frankly confess to being completely baffled by Shirley Jackson’s ‘The Lottery,’ ” she wrote in a letter to the editor after reading the story. “Will you please send us a brief explanation before my husband and I scratch right through our scalps trying to fathom it?”

Friend’s note was among the first of the torrent of letters that arrived at The New Yorker in the wake of “The Lottery”—the most mail the magazine had ever received in response to a work of fiction. Jackson’s story, in which the residents of an unidentified American village participate in an annual rite of stoning to death a person chosen among them by drawing lots, would quickly become one of the best known and most frequently anthologized short stories in English. “The Lottery” has been adapted for stage, television, opera, and ballet; it was even featured in an episode of “The Simpsons.” By now it is so familiar that it is hard to remember how shocking it originally seemed: “outrageous,” “gruesome,” or just “utterly pointless,” in the words of some of the readers who were moved to write. When I spoke to Friend recently—she is the only one of the letter writers I could track down who is still alive—she still remembered how upsetting she had found “The Lottery.” “I don’t know how anyone approved of that story,” she told me.

In a lecture Jackson often gave about the story’s creation and its aftermath, which was published posthumously under the title “Biography of a Story,” she said that of all the letters that came in that summer—they eventually numbered more than three hundred, by her count—only thirteen were kind, “and they were mostly from friends.” The rest, she wrote with mordant humor, were dominated by three main themes: “bewilderment, speculation, and plain old-fashioned abuse.” Readers wanted to know where such lotteries were held, and whether they could go and watch; they threatened to cancel their New Yorker subscriptions; they declared the story a piece of trash. If the letters “could be considered to give any accurate cross section of the reading public … I would stop writing now,” she concluded.

As Jackson’s biographer, I’ve pored over more than a hundred of these letters, which she kept in a giant scrapbook that is now in her archive at the Library of Congress. There were indeed some cancelled subscriptions, as well as a fair share of name-calling—Jackson was said to be “perverted” and “gratuitously disagreeable,” with “incredibly bad taste.” But the vast majority of the letter writers were not angry or abusive but simply confused. More than anything else, they wanted to understand what the story meant. The response of Carolyn Green, of New Milford, Connecticut, was typical. “Gentlemen,” she wrote, “I have read ‘The Lottery’ three times with increasing shock and horror.… Cannot decide whether [Jackson] is a genius or a female and more subtle version of Orson Welles.”

One of the many who took the story for a factual report was Stirling Silliphant, a producer at Twentieth Century-Fox: “All of us here have been grimly moved by Shirley Jackson’s story.… Was it purely an imaginative flight, or do such tribunal rituals still exist and, if so, where?” Andree L. Eilert, a fiction writer who once had her own byline in The New Yorker, wondered if “mass sadism” was still a part of ordinary life in New England, “or in equally enlightened regions.” Nahum Medalia, a professor of sociology at Harvard, also assumed the story was based in fact, though he was more admiring: “It is a wonderful story, and it kept me very cold on the hot morning when I read it.” The fact that so many readers accepted “The Lottery” as truthful is less astonishing than it now seems, since at the time The New Yorker did not designate its stories as fact or fiction, and the “casuals,” or humorous essays, were generally understood as falling somewhere in between.

Among those who were confused about Jackson’s intentions was Alfred L. Kroeber, an anthropologist at the University of California, Berkeley. “If Shirley Jackson’s intent was to symbolize into complete mystification, and at the same time be gratuitously disagreeable, she certainly succeeded,” he wrote. In an e-mail to me, Kroeber’s daughter, the novelist Ursula Le Guin, who was nineteen years old when “The Lottery” appeared, recalled her father’s reaction: “My memory is that my father was indignant at Shirley Jackson’s story because as a social anthropologist he felt that she didn’t, and couldn’t, tell us how the lottery could come to be an accepted social institution.” Since Jackson presented her fantasy “with all the trappings of contemporary realism,” Le Guin said, her father felt that she was “pulling a fast one” on the reader.

There were some outlandish theories. Marion Trout, of Lakewood, Ohio, suspected that the editorial staff had become “tools of Stalin.” Another reader wondered if it was a publicity stunt, while several more speculated that a concluding paragraph must have been accidentally cut by the printer. Others complained that the story had traumatized them so much that they had been unable to open any issues of the magazine since. “I read it while soaking in the tub … and was tempted to put my head underwater and end it all,” wrote Camilla Ballou, of St. Paul.

Even the New Yorker staff could not agree about “The Lottery.” The editors accepted it almost unanimously, the sole dissenter being William Maxwell, who found it “contrived” and “heavy-handed.” Brendan Gill, then a young staffer, told Jackson that the fiction editor Gus Lobrano, unsurprisingly, loved it, but reporters Joseph Mitchell, A. J. Liebling, and others were less impressed. (Gill thought it was “one of the best stories—two or three or four best—that the magazine ever printed.”) Harold Ross, the magazine’s editor at the time, never went on record with his personal opinion. But he wrote to Jackson’s husband, the literary critic and New Yorker staff writer Stanley Edgar Hyman, the following month that “the story has certainly been a great success from our standpoint.… [The cartoonist] Gluyas Williams said it is the best American horror story. I don’t know whether it’s that or not, or quite what it is, but it was a terrifically effective thing, and will become a classic in some category.”

The largest proportion of the respondents admired “The Lottery,” even if they did not believe they understood it. Arthur Wang, then at Viking Press and later to found the publishing house Hill and Wang, wrote to Hyman: “We discussed the story for almost an hour the other evening. It’s damned good but I haven’t met anyone who is sure that they … know what it’s about.” Nelson Olmsted, a producer at NBC, wrote to Jackson that he was interested in using the story on television. “I deal with hundreds of stories every year, but it has been a long time since I have seen one create as much interest and discussion as ‘The Lottery,’ ” he wrote. His own interpretation was that “humanity is normally opposed to progress; instead, it clutches with tenacity to the customs and fetishes of its ancestors.” (NBC ended up adapting “The Lottery” for two programs in the early nineteen-fifties.)