America at Large: When Arthur Bremer shot George Wallace at a presidential campaign rally in Maryland in the spring of 1972, the widespread assumption was that it portended some wider, deep-rooted conspiracy, and we all sprang into action. By nightfall I was at Hunter S Thompson's house in Washington, where he had recently been dispatched as National Affairs editor for Rolling Stone, writes George Kimball

Four of us were working the story for two different countercultural publications, and decided that our initial legwork could be accomplished most efficiently by a shared delegation of responsibility.

Francie Barnard, another Boston Phoenix reporter, and I spent the next day re-tracing the steps of the would-be assassin and the segregationist Alabama governor through the Washington suburbs. Hunter and his Rolling Stone cohort Tim Crouse would, in the meantime, work the story from their end by interviewing campaign and federal sources.

When Francie and I returned that evening laden with notes and taped interviews with the Maryland constabulary, we discovered Thompson and Crouse in the back garden, both half-stoned and sipping cocktails. They'd never left the house.

I was reminded of that evening a few years later with George Plimpton's account of the 1974 Muhammad Ali-George Foreman fight in Zaire. Thompson and another cohort, Bill Cardoso, had travelled to Africa to chronicle the event, and then spent a month wandering about The Dark Continent after Foreman's training-camp cut forced a month's postponement. By the time the fight took place, Thompson had contracted malaria and decided to skip the trip to the stadium. When Plimpton and Norman Mailer arrived back at their hotel the morning after The Rumble in the Jungle, they discovered Hunter floating naked in the pool.

"Who won?" he asked.

By then, of course, Hunter's legend had been firmly established. Having invented a public persona, he was then forced to endure three decades of trying to justify it. Thirty years of trying to be Hunter Thompson would have constituted an impossible task for any human, and in the end it consumed him.

I'd first met Hunter in 1968 when he walked into the offices of the Scott Meredith Literary Agency around the publication date of The Hells Angels, but even then his legend had preceded him. I was at the time subletting an apartment from the poet and translator Paul Blackburn, who'd just received a Guggenheim grant to go off to Spain. Paul's wife, Sara, was an editor at Random House who had midwifed the sale of Hunter's book, so I had advance warning that this wild man who'd just walked in off the New York streets with a cowboy hat perched on his head might be a kindred spirit.

After The Hells Angels became a surprise best-seller, Hunter began to have second thoughts about the contract he'd signed with Random House, which essentially gave the publisher an option on his next book on the same terms - including the same paltry advance - as the first. When the publisher stood firm, Hunter countered by submitting a manuscript of The Rum Diary, a terrible first novel which had been collecting rejection slips for a decade. The issue degenerated into lawsuits and countersuits, and Scott Meredith, though nominally the author's agent, covertly sided with the publisher, having erroneously concluded that he'd have to deal with Random House a lot longer than he'd have to deal with Hunter Thompson. Meredith had for years been indulging Mailer's eccentricities, and figured Thompson couldn't be any worse. He figured wrong.

With the issue pending in the courts, Scott Meredith began to withhold money due Hunter for ancillary rights, including foreign sales, from the Hell's Angels book. Although I was a very junior editor at the agency, I was able to function as Thompson's mole, staying after hours to furtively photocopy documentation of the foreign-rights sales and passing the information to Hunter and his lawyers. Meredith never did figure how Thompson was securing his background intelligence.

That episode ended badly. The Blackburns preceded their European trip with a visit to an arts institute in Aspen, where one evening Paul caught Sara in flagrante with Hunter, precipitating a divorce. Paul went off to Spain by himself, so I got the apartment for an extra year, Random House didn't get its second book and Hunter never did recover all his Hell's Angels money.

A year or two later we were both writing for the short-lived Scanlan's Monthly. A blown Playboy assignment covering the Kentucky Derby in the company of British artist Ralph Steadman wound up in the pages of Scanlan's, giving birth to what Cardoso would christen "gonzo" journalism.

If the tour de force was considered an act of genius, Hunter's own recollection was probably more accurate.

"I'd blown my mind, couldn't work," he once told an interviewer. "So finally I just started jerking pages out of my notebook and numbering them and sending them to the printer. I was sure it was the last article I was ever going to do for anybody."

Even while relentlessly developing the persona, he struggled to maintain a sensible demarcation with his private life. In 1969, I drove to Aspen with my brother and another friend. When I phoned Hunter, he instructed me to drop my companions in town and to visit alone. I spent several pleasant hours enjoying the quiet hospitality of Hunter, his then-wife Sandy, and his young son, Juan, after which we rejoined the others at the Hotel Jerome bar, where, as if on cue, he transformed himself and spent the rest of the evening dutifully performing his Dr Gonzo act. We stayed up all night, and greeted the dawn sitting on his back porch in Woody Creek plinking - if you can call blasting away with a .44 Magnum "plinking" - at an elaborate configuration of gongs he had set up on the fence abutting his property.

By 1970, we were each involved in a countercultural run for the sheriff's office: I was on the ballot in Douglas County, Kansas, Thompson ran in Pitkin County, Colorado. We had arrived at our decisions independently, but, once nominated in our respective jurisdictions, we did hold a summit meeting of sorts that summer.

"George Kimball just left after a vicious three-day strategy session," Hunter reported in a letter to Realist editor Paul Krassner that August. "He's running for sheriff of Lawrence, Kansas, but with no hope of winning. This is a strange phenomena . . . with no prior collusion. Very odd."

By 1971, Hunter had assumed his post at Rolling Stone. Having relocated to Massachusetts, I occasionally covered music for the same publication. That spring I got a letter from Hunter (re-published in Fear and Loathing in America) which began: "George, I've just been talking to Jann Wenner about you, suggesting that he get you into writing some articles in addition to that record-review gig. My motives were mixed, of course. Aside from your undeniable mastery of the medium, I want Wenner to have the experience of dealing with somebody more demonstrably crazy than I am - so that he'll understand that I am, in context, a very responsible person."

Being described as more nuts than Hunter S Thompson, even by Hunter S Thompson himself, was a pretty frightening thought.

At Rolling Stone Hunter wore two hats: his own, and that of "Raoul Duke, Sports Editor". In this latter connection we covered two Super Bowls together. For the first, the 1973 game between the Dolphins and the Redskins, we stayed for a week with Cardoso and his wife at their Hollywood house, thereby presaging the break-up of yet another marriage.

A year later we covered Super Bowl VIII in Houston. There took place the Battle of the Blue Fox, in which, to Thompson's delight, we watched a pair of undercover cops subdue an entire pool-cue and broken-bottle-wielding motorcycle gang when a brawl broke out in a Texas strip joint.

Another night that week, Thompson sat in a Houston saloon and produced a sheet of paper from one pocket and a Swiss army knife from the other, depositing the resultant bits of confetti into his drink. When Leigh Montville, then of the Boston Globe, asked me what he was doing, I replied, correctly, "blotter acid". Montville groaned. Hunter was supposed to be our designated driver that night.

We managed to make it safely back to the hotel before the chemicals kicked in, but later that night, grabbing a religious tract which had been slipped under his door, Thompson delivered a thundering homily, roaring out Biblical passages from the 14th floor of the atrium at the Houston Hyatt Regency.

One night in the early 1970s, someone with an odd sense of humour invited Hunter and me, along with the venerable Boston Globe columnist George Frazier, to address a gathering of the Nieman Fellows over dinner at a Back Bay gentlemen's club. Attuned to Thompson's tastes, the Harvard undergraduate charged with shepherding us through the procedure had thoughtfully provided a quart of Wild Turkey, which was long gone even before the cocktail hour commenced, with predictably disastrous results.

The next morning Hunter and I excused our comportment by reflecting that we had, after all, behaved pretty much the way the Niemans had expected us to behave, but poor Frazier was so traumatised by the evening that for the remaining few years of his life he winced in mortification whenever it was mentioned.

Another botched assignment - this time to cover a convention of police chiefs in Sin City for Rolling Stone - turned, quite by accident, into a masterpiece. When Fear and Loathing in Las Vegas appeared in 1973, no one had read anything quite like it, and, alas, they never would again. It was by far the best thing Thompson wrote, and he spent the rest of his days in a vain attempt to re-achieve that promise while simultaneously attempting to fulfil the expectations of the doting cult of worshippers he had unwittingly spawned.

There had been only sporadic contact in recent years, but when my daughter moved to Colorado last month I did give her Hunter's number and e-mailed him that he might expect a phone call.

Last Sunday Hunter killed himself with a bullet through the head. Juan found the body when he stopped by the house the next morning. There will be those who will now try to claim that Hunter, who always lived for today without a thought for tomorrow, left this earth on those very terms.

My daughter phoned from Denver when she heard the news.

"I never did get to meet him," she said. "I'm sorry now that I didn't at least call."

"It wouldn't have made much difference," I told her. "I guess he just wanted to prove how crazy he really was."