One morning in February 1952, in a holiday hideaway on the island of Jamaica, a middle-aged British journalist sat down at his desk and set about inventing a fictional secret agent, a character that would go on to become one of the most successful, enduring and lucrative creations in literature. Ian Fleming had never written a novel before. He had tried his hand at banking, stockbroking and working as a newspaper correspondent. Only during the war, as an officer in naval intelligence, had he found a task – dreaming up schemes to bamboozle the enemy – worthy of his vivid imagination. By 1952, he had settled into a job as a writer and manager on The Sunday Times, a role that involved some enjoyable travel, a little work and a lot of golf, women and lunch. Even his best friends would have snorted at the notion that Ian Fleming was destined for immortality.

This, then, was the man who, after a morning swim to sluice out the hangover of the night before, hunched over the desk in his Jamaican home, “Goldeneye”, and began to type, using six fingers, on his elderly Royal portable typewriter. The opening line would read: “The scent and smoke and sweat of a casino are nauseating at three in the morning…” Fleming wrote fast, the words pouring out at the rate of 2,000 a day. A month after he had started writing, he tapped out the words “…‘the bitch is dead now’.” Casino Royale was complete, and James Bond was born.

All novelists find inspiration in reality, but Ian Fleming, more than most, firmly anchored the imagined world of James Bond to the people, things and places he knew. The characters, plots, places, machines and situations in the James Bond stories are so firmly embedded in fact that it is often hard to spot where the real world of Ian Fleming ends and the fictional world of James Bond begins. Espionage is itself a shadowy trade between truth and untruth, a complex interweaving of imagination, deception and reality. As a former intelligence officer, Fleming thought like a spy, and wrote like one.

Like the character he had created, Ian Fleming was a great deal more complex than he seemed on first acquaintance. Beneath the sybaritic exterior, he was a driven man, intensely observant, with an internal sense of romance and drama that belied his public languor and occasional cynicism. Bond is, in part, Fleming, and the exploits of 007 grew directly out of Fleming’s knowledge of wartime intelligence and espionage: he would teasingly refer to the Bond books as “autobiography”. Like every good journalist, Fleming was a magpie, collecting material avidly and continuously: names, places, plots, gadgets, faces, restaurant menus and phrases; details from reality that would then be translated into fiction. He once remarked, “Everything I write has a precedent in truth.”

But Bond is also, in part, what Fleming was not. He was the fantasy of what Fleming would like to have been – indeed, what every Englishman raised on Bulldog Drummond and wartime derring-do would like to have been. Bond is a grown-up romantic fairytale, a promise that Britain, having triumphed in the World War, was still a force to be reckoned with in the dull chill of the Cold War. In the grim austerity of postwar Britain, here was a man dining on champagne and caviar, enjoying guiltless sex, glamorous foreign travel and an apparently unlimited expense account.

Thirteen more Bond books would follow Casino Royale. By the time of his death, just 12 years later, Ian Fleming had sold more than 40 million copies, and given birth to a multibillion-dollar film industry. Today, more than half the world’s population has seen at least one Bond film. Even at the height of his fame, Fleming maintained an airy attitude toward his books. “I extracted them from my wartime memories,” he remarked, “dolled them up, attached a hero, a villain and a heroine, and there was the book.” This nonchalance was the purest bluff, something that Fleming, as a lifelong card-player and intelligence expert, was very good at. The idea for Bond had been gestating in his mind, and his personality, for at least a decade. Back in 1944, Fleming had told a friend in deep earnestness, “I am going to write the spy story to end all spy stories.”

And that is exactly what he did.

Who was James Bond? Every acquaintance of Ian Fleming ran the risk of ending up in one of his Bond books, and almost every character in his fiction is based on a real person, even if only by name. He plucked these monikers from his social circle, his memory, his reading, his favourite newspaper, the Jamaica Gleaner, and his imagination: old school friends (and enemies), clubmen, colleagues in the City and Fleet Street, golfing partners, girlfriends and others found themselves transported into Fleming’s fiction. There are several theories as to the origin of the name James Bond. The most popular (and one that he publicly affirmed) is that Fleming, sitting down to work at his desk in Goldeneye, simply lifted the name from his bookshelves, his eye having alighted upon Field Guide to Birds of the West Indies by James Bond, the standard reference book.

People were named after things, and things were named after people. His lover in later life, Blanche Blackwell, gave him a small boat named Octopussy, which became the name of a man-eating pet octopus in the short story. In rather ungallant return, Fleming named the ancient guano tanker in Dr No the Blanche. The crime boss Marc-Ange Draco in On Her Majesty’s Secret Service is named after El Draco, the Spanish name for Sir Francis Drake – a reference picked up years later by J. K. Rowling for her Hogwarts antihero, Draco Malfoy. Rosa Klebb (the Russian for bread) was partly based on Colonel Rybkin of Soviet intelligence. Major Boothroyd, the secret service armourer, is named in honour of Geoffrey Boothroyd, the gun expert who provided Fleming with invaluable technical advice.

Like most fictional characters, James Bond is not one individual. “He was a compound of all the secret agents and commando types I met during the war,” Fleming once declared. Chief among the contenders is, of course, Fleming himself. The physical descriptions of 007 recall his creator, with his “longish nose” and slightly “cruel mouth”. Fleming sometimes played up the autobiographical aspects of Bond, and sometimes downplayed them. “I couldn’t possibly be James Bond,” he told a friend. “He’s got more guts than I have. He’s also considerably more handsome.” Peter Fleming, Ian’s hero-worshipped elder brother, may have come a little closer to that model, being good-looking, cultured, tough and, most importantly, a secret agent, having been drafted into the world of military intelligence and irregular warfare early in the war.

Behind the Flemings follows a parade of swashbuckling types, each with a claim to a little of the Bond myth: Conrad O’Brien-Ffrench, a spy Fleming had first met on the Austrian ski slopes in the Thirties when the older man was gathering information on German troop deployments as part of an amateur spy network made up of journalists and businessmen. Another strong candidate is Patrick Dalzel-Job, who served in the intelligence commando unit Fleming helped to establish in the latter part of the War. Dalzel-Job was a superb marksman who could ski backwards, parachute behind enemy lines and pilot a miniature submarine. On assignment, he wore an airman’s jacket with a compass hidden inside one of the buttons, and smoked a pipe with a hidden map-chamber. Serving in Norway in 1940, Dalzel-Job revealed a Bond-like streak of rebellion when he disobeyed a direct order and insisted on evacuating 5,000 Norwegian civilians from the town of Narvik who were facing imminent Nazi retaliation. By the time Fleming met him in 1944, Dalzel-Job had won a reputation for bravery just this side of lunacy. Throughout his long life, Dalzel-Job was credited with being the model for James Bond. He never denied the association, but disarmingly pointed out: “I have never read a Bond book or seen a Bond movie. They are not my style… And I only ever loved one woman, and I’m not a drinking man.” Other contenders include Michael Mason, a fur-trapper and successful boxer who operated as an agent in Romania during the war. Also Wilfred “Biffy” Dunderdale, the station chief of SIS (MI6) in Paris, whom Fleming met in 1940. A regular at Maxim’s on the Rue Royale, exquisite in Cartier cufflinks and handmade suit, driving an armour-plated Rolls-Royce through Paris, Dunderdale had much of Bond’s style.

The real “M” may be easier to identify. The fictional Admiral Sir Miles Messervy KCMG is based, in large part, on Admiral John Godfrey, Fleming’s boss at the Naval Intelligence Department. M is grumpy, rude and every inch the naval martinet, with “damnably clear” bright blue eyes; his underlings are terrified and loyal in equal parts. All these traits were apparent in Godfrey. Fleming described him as a “real war-winner”. The admiral would eventually ask Fleming to write his biography (Fleming declined), yet it seems the inspiration for M was not entirely pleased to be immortalised as the boss of a cold-blooded killer. “He turned me into that unsavoury character, M,” Godfrey complained after Fleming’s death.