We’re all familiar with those classic poster images of Mr James Dean, staples of student dorms the world over: he’s flâneur-ing his way through a rain-swept Times Square, shoulders hunched, the collar of his double-breasted greatcoat upturned against the drizzle, a cigarette defiantly blazing in or somewhere near his lips. They’ve established Mr Dean in the public consciousness as the eternal embodiment of the loner and rebel, but it was the way he wore that rebellion – slouchy, louche, proto-Boho – that made him a menswear exemplar and a shoo-in for our fall/ winter 2014 Very MR PORTER campaign.

His indelible look is one reason that, nearly 60 years after his untimely death, Mr Dean remains one of cinema’s favourite poster boys. Another reason is his die-young-stay-pretty body of work – just three films, Rebel Without a Cause, East of Eden and Giant – in which he established the blueprint of tortured teenage style. He took the brooding, sensitive masculinity pioneered on screen by Mr Marlon Brando to a whole new emo-boy-outsider level.

“The James Dean archetype is just as relevant today as it once was,” says Mr Parker Ellerman, director of Friendly Ghosts, a film project aiming to explore Mr Dean’s lingering influence on modern culture. “Many of our [more recent] icons, such as Brad Pitt, Ryan Gosling and the late Kurt Cobain, share the same quintessential nonchalance and rebellious style that are emblematic of Dean’s magnetic legend.”

That style, as reflected in Mr Dean’s insouciant, ground-breaking ensembles – white T-shirts, broken-in jeans, biker jackets, Breton sweaters – fully justified the claim made for Mr Dean in the posthumously released Giant: “the star who became a legend, who spoke for the restless young as no one has before or since”. He continues to speak for the restless young and the restless young at heart.

The teenager was effectively born in 1955, when Mr Dean dazzled adolescent audiences as Jim Stark in Rebel Without a Cause, which follows a trio of misfits – his fellows are played by Ms Natalie Wood and Mr Sal Mineo – and their various conflicts with authority. Mr Dean’s look in this film – red blouson jacket, white T-shirt, dark denim, messy quiff – embodied his celebrated axiom: “Dream as if you’ll live forever, live as if you’ll die today.”

“Jimmy represented something that was happening in the US after WWII,” says Mr Dean’s friend and contemporary, the actor Mr Martin Landau. “Until that moment in time, grown-ups – adults – set the styles for clothing, set the styles for music, set the styles for everything that was going on.”

Mr Dean’s look and performance – stark, mordant, impassioned – swept that aside. The film’s costume designer, Mr Moss Mabry, reportedly found the inspiration for Mr Dean’s look in a Life magazine feature, which featured a group of young college students. The film’s director, Mr Nicholas Ray, was deeply interested in the psychology of colour, appointing a hue to each character; Mr Dean’s reds and deep blues (his jeans were dip-dyed to accentuate the indigo’s vibrancy) expressing Jim Stark’s aura of danger and inner conflict.

Mr Dean was as sartorially mould-breaking off-screen as on. In an era still hidebound by traditional notions of Hollywood glamour, his casual but calculated approach to dress – the crumpled rollnecks, the unbuttoned chambray shirts, the slouchy overcoats, the artfully disarranged evening dress, the thick glasses he wore for near-sightedness – represented a one-man insurgency against conformity. Mr Dean sourced his core pieces from Mattson’s on Hollywood Boulevard – a department store he’d been turned on to by Mr Frank Mazzola, an LA gang member who’d served as “technical adviser” on Rebel Without a Cause – and supplemented his look with judicious thrift-store buys. He pioneered a rugged edge to fashion that would be appropriated by Mr Elvis Presley (who idolised Mr Dean and took up acting in an attempt to follow in his footsteps) and referenced by every subsequent youthquake, from the beats to the mods to the punks. Even that noted iconoclast Mr Bob Dylan reportedly adopted a red jacket as an homage to Mr Dean, while the ongoing ubiquity of the white vest can be traced back to Mr Dean’s popularising of the garment in 1956’s Giant.

Mr Dean also mixed casual and formal elements to great effect, pairing a dinner jacket with a pair of scuffed work boots, for example. (He’d been raised on his extended family’s farm in Indiana, loved nature and never quite lost his lonesome-ranch-hand air.) “Only the gentle are ever really strong” was another of his mantras, and his look helped project an image of openness and vulnerability. “The main actors of that time – Clark Gable, John Wayne – were ramrod-straight men who spoke very clearly,” according to the esteemed playwright Mr Tennessee Williams. “Dean cut through all that. He was a rare combination of deep sexuality and deep sweetness.”

“What better way to die?” Mr Dean once eulogised on the subject of racing cars. “It’s fast and clean and you go out in a blaze of glory.” He seemed to sense that he wouldn’t be around for too long, packing an awful lot into his 24 years. He reportedly had affairs with men and women (from screenwriter and former roommate Mr Bill Bast to young Italian actress Ms Pier Angeli) and was equally sophisticated in his other tastes (he eulogised classic composer Mr Béla Bartók and jazz singer Ms Billie Holiday, and he broke off a date with Ms Ursula Andress to play drums in a jazz club).

He purchased a Triumph Tiger T110 motorcycle, trading it for a Triumph TR5 Trophy three days after filming wrapped on East of Eden. But it was the “liberating prospects” of motor racing that really enticed him. He entered the Palm Springs Road Races in a Porsche Super Speedster in March 1955, and was scheduled to compete at an event in Salinas, California, that October. It was while preparing for the latter that Mr Dean was involved in his fatal crash.

He might be Hollywood’s darkest cautionary tale, but the edge-play in his personal and professional life has only compounded his imperishable allure. “He was always himself, and quietly assured in the way he dressed and presented himself, and people continue to respond to that,” says Mr Ellerman. “Plus, you never see a bad photo of him, and how many people can you truly say that about?”

“What I remember most about him was the little boy quality shining forth at you from behind those thick glasses of his, tearing at your heart,” said the legendary movie columnist Ms Louella Parsons. “He had that extreme and touching idealism of youth which made you wish that he would never have to be disillusioned. Now he won’t be.”

Mr Dean himself once averred that “the only greatness for man is immortality”. As a continuing pop-culture colossus and a perennial style icon, it’s safe to say that, by his own yardstick, his place among the greats is assured.