Censorious spirits might say that the writer and satirist William Donaldson, who has died aged 70, repeatedly took the wrong path. He lost a couple of fortunes, lived in a brothel, had many affairs and, in his 60s, ingested crack cocaine. That said, he is rightly best known as the perpetrator of a great literary hoax.
The Henry Root Letters (1980) was a collection of correspondence between the supposedly retired wet-fish merchant, Root, whose clever if unhinged jottings to the great and the good, often enclosing small sums of money, elicited some wonderfully revealing responses. They were, of course, penned by Donaldson. He was also co-producer of Beyond The Fringe, an early promoter of Bob Dylan and the author of Brewer's Rogues, Villains And Eccentrics (2002).
Donaldson lived by the seat of his pants - which were often cast aside, for his abundant good humour, the ultimate aphrodisiac, brought him more than a dalliance with the actor Sarah Miles and the singer Carly Simon. They were among the many who did not become one of his three wives.
Brought up in a huge house in Sunningdale, Berkshire, Donaldson was given a 12-bore shotgun at the age of 11 by his father, who owned a shipping line. "Since it was as big as I was, its kick when I let it off lifted me 20 yards backwards into a ditch," he recalled. A more formative experience was persuading his parents to take him, when he was a Winchester College schoolboy, to the Folies Bergère.
He did his national service in the navy, spending much of his shore leave with his friend, the future playwright Julian Mitchell, who insisted that they visit as many art galleries as possible. Not that this precluded Donaldson from losing his virginity to a Parisian prostitute.
He was reading English at Magdalene College, Cambridge, in the early 1950s when his father died, leaving him, suddenly, very rich (his mother had died in a car crash two years earlier). He was soon spending his inheritance, supporting student literary magazines, such as those in which the work of the young Ted Hughes and Sylvia Plath appeared.
Upon his graduation, Donaldson became part of the Princess Margaret crowd, and moved into theatrical production. This period included a first, if brief, marriage, to Sonia Avory in 1957, and the birth of his only child, Charlie. His footloose spirit then garnered a succession of affairs, including Miles.
Professionally, his most notable theatrical venture was as co-producer (with Donald Albery) of Beyond The Fringe (1960), from which they each took £2,000 a week - to the consternation of the cast, Peter Cook, Dudley Moore, Alan Bennett and Jonathan Miller, who were on £75 each. He also produced JP Donleavy's The Ginger Man (1959) and Spike Milligan's The Bed-Sitting Room (1963) .
Even so, Donaldson's fortune ebbed, a trend not helped by having to finance Dylan's appearance at Cook's Soho club, the Establishment (according to Donaldson, his friend, the music producer George Martin, turned down the singer's tape). Music continued to play a part in Donaldson's life when, two days after leaving Miles in the mid-1960s, he took up with Carly Simon - "the answer to any sane man's prayers; funny, quick, erotic, extravagantly talented".
Nor did his sexual whirlwind stop when he married the actor Claire Gordon in 1968, their house becoming a quintessential 1960s stop-over. As he later recalled: "Sex, whether in company or not, has been the only department in life in which I have demanded from anyone taking part the very highest standards of seriousness."
In 1971, Donaldson went to Ibiza. Down to £2,000, he spent it on a glass-bottomed boat. Back in London, he lived at a friend's brothel off the Fulham Road, which inspired his first novel, Both The Ladies And The Gentlemen (1977). Then, by the decade's end, and married to Cherry Hatrick, came The Henry Root Letters, which netted him some £100,000.
Among those in receipt of the famed Root correspondence were Esther Rantzen, Nigel Dempster, the first sea lord, Root's hero, the prime minister Margaret Thatcher, and the young Harriet Harman, then at the National Council for Civil Liberties. Root advised "a pretty girl like you" to read the news or go on stage, enclosed a pound note for "a pretty dress" and suggested she ring "my friend Lord Delfont".
He also wrote to the senior Treasury counsel at the Old Bailey: "Now that the sensible practice of jury fixing is out in the open thanks to the irresponsible behaviour of the Guardian, I would like to nominate myself as a rigged juryman in certain trials. In cases involving pornographers, blasphemers and those prone to civil agitation and disorder, you'd have at least one vote under your belt ... Here's a pound! Put my name at the top of the list if you want a conviction!" The money was returned.
None of Donaldson's other works had anything like the commercial success of Root. Among them were The English Way Of Doing Things (1984); a crowded, muddled novel, Is This Allowed? (1987) and a television series, Root Into Europe. Another spoof series about proposed soaps was Heart Felt Letters (1998). He also extended the spirit of his newspaper column in the Independent into an account of modern manners and pretensions, I'm Leaving You, Simon, You Disgust Me (2003).
Avowedly chaotic, but blessed with a formal manner, Donaldson stumbled after his true métier, the right outlet for a wide and interesting knowledge fortified by concentric circles of friends. In his memoirs, From Winchester To This (1998), he recounts how, in 1985, he went back to Ibiza, enthralled by another young woman, and got a taste for crack cocaine. He insisted he was not an addict, though he appears to have used it for more than a decade.
His last book, the 700-page Brewer's Rogues, Villains And Eccentrics, was a repository of much fascinating, arcane lore, as well as entries for Brooklyn Beckham and the Duke of Edinburgh, all built upon a fiendishly entertaining system of indexing and cross-references. It was perhaps the book he was always destined to write.
He is survived by Cherry, from whom he was separated, and by his son.
Richard Milbank, of Weidenfeld & Nicolson, writes: Willie Donaldson warmed instantly to the suggestion that he should write a dictionary of Rogues, Villains And Eccen- trics. He knuckled down to two years' research and writing, and delivered - bang on time - 300,000 words of the most elegant, informative and understatedly humorous prose. All were entranced by what one reviewer described as "a breathtaking triumph of misdirected scholarship".
Willie's Flaubert-inspired Dictionary Of Received Ideas - I'm Leaving You Simon, You Disgust Me, followed in 2003, delighting Donaldson devotees but baffling others. Enraged by the absurdity of a culture dumbed down by the media, he was working, with Hermione Eyre, on a Dictionary Of National Celebrity at the time of his death.
Willie's conduct as a writer, while always playful, somewhat belied his image of a chaotic and irregular life. He was respectful of deadlines, receptive to editorial suggestion and meticulously correct in matters of style and presentation.
· William Donaldson, writer, born January 4 1935; died June 22 2005