Fifty years after the publication of Fear and Loathing in Las Vegas, Hunter S. Thompson’s celebrity remains a durable fact. Yet there was nothing inevitable about his notoriety or the style that gave rise to it. Gonzo journalism—Thompson’s unique blend of hyperbolic commentary, satire, invective, hallucination, and media critique—developed unevenly, haphazardly, almost by accident. That body of work, and the rock-star celebrity it created, almost didn’t happen.

In 1965, Thompson was a freelancer begging for assignments when The Nation commissioned an article on the Hell’s Angels motorcycle gang. Thompson parlayed his first-person account into a bestselling book, and Random House quickly signed him for three more titles on short schedules. The second book stalled, however, and Thompson struggled with his magazine work. Playboy spiked his lengthy profile of Jean-Claude Killy, the Olympic skier who became a pitch man for Chevrolet. Fortunately for Thompson, Warren Hinckle ran the Killy piece in the premiere issue of Scanlan’s Monthly.

Hinckle also published “The Kentucky Derby Is Decadent and Depraved,” Thompson’s 1970 account of the famed sporting event—or rather, the drunken revelry surrounding it. Illustrated by Ralph Steadman, that piece is usually considered the first work of gonzo journalism. Thompson set the debauchery at Churchill Downs against a backdrop of political violence—including President Nixon’s bombing of Cambodia and the slaughter at Kent State University, which occurred the same week as the Derby. Finishing the story was an ordeal, and Thompson considered it an abject failure. When it was heralded as a breakthrough, he compared the experience to “falling down an elevator shaft and landing in a pool full of mermaids.”

Thompson’s next articles skipped the gonzo pyrotechnics, but “Fear and Loathing in Las Vegas,” which Rolling Stone ran in November 1971, etched gonzo journalism in the public imagination. Based on a pair of wild weekends in the desert, the two-part article was a freewheeling epitaph for the 1960s counterculture. It made a bigger splash than the Kentucky Derby piece, but in a letter to James Silberman, his editor at Random House, Thompson worried that it would diminish his credibility as a serious journalist. Once again, he had underestimated gonzo’s career-altering appeal.

Gonzo journalism thrived at Rolling Stone, especially during the Nixon era. As the decade wore on, Thompson’s outsize persona—which featured his drug consumption, gun fetish, and “fortified compound” near Aspen—began to eclipse his work. Yet Thompson understood his literary gift quite apart from his celebrity. In 1975, he correctly described himself as “one of the best writers currently using the English language as both a musical instrument and a political weapon.”