Even if you are as one with Lily (“Madonna is the most overrated person in pop history”) Allen, there is something satisfyingly perverse about seeing her clothes become, in these topsy-turvy economic times, the stuff of investors’ dreams. At any rate, two venture capitalists, with an eye to future riches, have spent the past two years tracking down her more memorable outfits, chasing up documentation to corroborate their provenance (you wouldn’t believe the number of fakes out there) and batting away rival collectors in the bidding wars.

The fruits, so far, tally some 250 items of clothing, plus another 50 or so pieces of Madonna ephemera, including awards, although perhaps they won’t prove so ephemeral. “I’m by no means a Madonna freak,” says Chetan Trivedi, one of the VCs, “but when you look at how wide her demographic is and how long she has been at the top, Madonna’s clothes start to look like a better bet than the stock market.” This is a point not lost on the Material One herself, who has a warehouse in Los Angeles where she stores the pieces she’s kept post-1993.

What makes this collection more visceral than most are the traces of the woman who wore them – make-up smudges on a beret, perspiration stains on one of the corsets worn in rehearsals. For the moment, the collection resides in the vaults of Coutts, but soon it will be unleashed in an exhibition. And for anyone with an interest in popular culture, it’s worth a look. Madonna’s assault on the world can’t properly be viewed outside the prism of the clothes she wore while mounting it. From the early scavenged props, through the dark Marlene years, when Madonna gender-bent and flashed more parts of her anatomy than seemed compatible with her status as a world superstar, to the pastel Juicy Couture jogging suits of the early Mummy years, from Geisha Girl to Braveheart, Latino sexpot to Marie Antoinette, voluptuous Marilyn to a 50-year-old leotard-toting, designer-bandage-sporting defier of gravity, fashion has been integral to her identity.

No one can accuse her of idleness. In 25 years she has developed a new kind of body to aspire to, one that arguably hands women power over their shape; extended the shelf life of gyrating female performers by two decades and counting; pushed female sexual boundaries to places that chart-topping female singers had never seen the need to drag them (granted, this wasn’t always a pretty sight); invited the gay scene to the mainstream party; experimented with most genres of pop and rock; defied social mores (then embraced them); and subjected herself to more image changes than a serial witness protection scheme participant.

Naturally, this was all entirely self-seeking – and not especially original. Arguably, her most creative fashion legacy, pieced together from fragments worn by Martha Graham dancers, the street and Madonna’s idiosyncratic twists, was the first public incarnation, made famous in the Like a Virgin video, then indelible in Desperately Seeking Susan. This rag-tag look endeared because it was accessible and yet distinctive, achieved without money. It captured an aspect of the Eighties that tends to be overlooked: the decade’s optimism, verve and spirit of DIY.

The other style moments, like her musical output, are generally the fruits of gifted larceny. She didn’t invent conical bras, any more than she came up with the concept of androgyny.

But she knew the right time to wear them – after the prototypes had been perfected, but before they’d lost their power to shock or surprise. And yet for all the thrusting and sexual provocation, she has never really been a (straight) man magnet. She’s way too terrifying, particularly during her gynaecologically obsessed period.

But if you’re a woman, if you’re gay, if you’ve ever enjoyed one of her songs or thought she looked nice dressed up as Eva Perón, if you’re one of scores of designers, from the global big shots to the unknowns, whom she patronised and subsequently put on the map, then you’ve been under the Madonna influence. Resistance may just be futile.

The exhibition Simply Madonna is at the Old Truman Brewery, London E1, from February 21 to March 31

Material Girl, 1985

Hiring a kitschly pink satin strapless dress for the video of Material Girl, Madonna openly plagiarised Monroe’s scene in Gentlemen Prefer Blondes. But where Monroe was part gold-digger, part adorable naif, Madonna is entirely knowing. This was a platinum blonde whose eyebrows were deliberately left a contradictory shade of charcoal and whose body was beginning to look as though she could go several rounds in the ring. Given that workout regime, Monroe wouldn’t be the later Madonna’s chosen screen reference – Dietrich would, and not the fleshy young Dietrich of the Lola era.

Attempting to put a twist on Anita Loos’ satire on materialism, Madonna, hair slickly waved, interspersed scenes from the 1953 movie with a new story that showed her playing an actress being wooed by a Hollywood director who has to pretend to be poor in order to win her (unmaterialistic) heart. Hah! Ironically, it’s Monroe who emerges as the more subversive.

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