When Vanity Fair was born in 1913, the precociously fresh monthly of the Condé Nast stable, it coincided with the birth of Modernism, the dawning of the Jazz Age and the Armory Show, which introduced avant-garde art to the American public. The magazine was designed to engage with this vibrant new culture, promoting new talents and ideas and everything that was at the forefront of change. From the outset, photography was heavily promoted on the page, given wide white margins and prominence in the layout.

Its star photographers, Baron de Meyer and Edward Steichen, backed by an impressive team of masterful practitioners, portrayed intellectual matrons such as Gertrude Stein and men of capacious brains such as Thomas Hardy, alongside glamorous cosmopolitan artistes like Nijinsky and Isadora Duncan. Already by 1929, in Nickolas Muray’s portrait of Douglas Fairbanks Jr and Joan Crawford, readers of Vanity Fair were being given a gorgeous eyeful of beauty, talent, glamour and fame. “That picture is one of my favourites,” says Vanity Fair editor Graydon Carter. “It’s so beautifully composed. It’s The Philadelphia Story in one image.”

Today, the focus has narrowed somewhat from this eclectic mix of artists, writers and players to the young and the beautiful: often mind-bogglingly rich professional actresses who “bleed” to the edge of the page in brilliant colour, their cheeks and lips ablaze in red and barely a stitch of clothing on their sleek, polished bodies. Keira Knightley and Scarlett Johansson, for example, photographed together by Annie Leibovitz in 2005, evoke a steamy eroticism as they arrange their naked limbs across a backdrop of black velvet, their arrogant mouths and hard eyes giving us a frankly appraising gaze.

In-between the two stretches the story of modern stardom, the rise of Hollywood to dazzle cinema audiences around the globe, its stars invading the public mind like a phantom army. Tracking Hollywood’s growth and celebrating its players was Vanity Fair, which presented its subjects as both human and superhuman, figures whom its readers could both identify with and worship. Its pages offered an experience somewhere between a brothel and a church: inside, fantasies could be hired for a short time and faith might be sealed for life.

Vanity Fair today has not strayed far from this formula. In the Thirties it was irreverent, snobbish and always entertaining, famously designed to ignite a dinner party at 50 yards. It is still irreverent, snobbish and entertaining, but also tightly focused on a permeable, democratic elite of looks, talent, taste, image, money and success.

In our age of rampant celebrity worship, its greatest strength lies in its inventive photographic portraits, which make icons of the high and mighty and provide something for our fantasies to work on. The selection of Vanity Fair portraits on show at the National Portrait Gallery makes it clear how a portrait in the magazine has become the emblem of a star’s public persona, shaping, defining and elevating their image, while also shaping America’s popular culture in the eyes of the rest of the world. “Getting your own photo shoot in Vanity Fair,” wrote Maureen Dowd in The New York Times, “has become the premier achievement in our celebrity-mad culture.”

“We basically invented modern photographic portraiture,” says Graydon Carter. “Before Vanity Fair, portraiture was so dusty and Edwardian. There’s a great history there. Vanity Fair produced the iconic image of many stars. Edward Steichen’s Paul Robeson portrait, for example, is the one we all know. It’s powerful, but also vulnerable in a way. And Cecil Beaton’s portrait of Katharine Hepburn. Even in today’s video assault world, we can show you the power of a still image. You walk away with an image that you will remember.”

“Photographers have become image definers in a way portrait painters used to be,” says David Friend, editor of creative development at the magazine. “Having a Vanity Fair portrait does signal that one has arrived.”

Vanity Fair closed in 1936, a victim of the Depression, and lay dormant for almost 50 years. The prince whose kiss reawakened the title in 1983 was Ronald Reagan. As a former actor, he had brought a dose of Hollywood glamour to the White House and, as Friend writes in the catalogue introduction, his reliance on image over depth mirrored that of American culture. His spin team mastered the photo op. His policies were parcelled out in sound bites.

His slogans were lifted from the movies. He understood that the electorate preferred surface to substance. In addition, a vibrant cosmopolitan spirit was coursing through American culture which was to become something of a mirror of the Jazz Age. It was the perfect moment for Condé Nast to relaunch the magazine.

Harry Benson was sent to photograph Ronald and Nancy Reagan. He had been offered a tiny slot before they went into a White House state dinner. “They put me in the Map Room and as soon as the door closed I rolled up the carpet, put the furniture aside, set up a white backdrop and I was all ready. When they came out of the elevator from their private quarters they walked in and my assistant turned on a record player playing Sinatra’s Nancy with the Laughing Face. He looked a bit bewildered, but she laughed and started to dance with him. You should have seen the look on the press secretary’s face. They couldn’t do anything about it. After a couple of minutes Reagan looked at his watch and said, ‘I’m keeping the President of Chile waiting.’ ‘Oh Ronnie!’ said Nancy. ‘Let him wait!’” He managed to coax six minutes from them, dancing, twirling, even kissing for the camera.

“That picture is what I saw. It was real, but these days with digital photography they move heads around, add people, change a girl’s legs if they don’t look right, change teeth if they’re not pretty enough. Just like Stalin who removed his enemies from photographs. These days, the enemies are the non-beautiful. It’s not photography, it’s photo-fiction,” says Benson.

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