He was born Jacob Benjamin Gyllenhaal (pronounced Jill-en-hall) on the 19th of December, 1980, in Los Angeles. His geneology, at least on his father's side, is fascinating, his family hailing from Sodra Harene, a parish of Vastergotland, inbetween Skara and Gothenburg in south-west Sweden. It's possible that he's descended from King Gustav I, who reigned between 1523 and 1560 and, due to his enlightened rule, was labelled the founder of modern Sweden. What's certain is that Jake's surname can be traced back to December 20th, 1652, when Queen Christina Wasa (played onscreen by Greta Garbo) ennobled his ancestor, cavalry officer Nils Gunnesson Haal for his efforts in the Thirty Years War, a bloody Europe-wide feud between Catholics and Protestants that saw the Swedes battle against the Danes and the Holy Roman Empire - "Gyllen", meaning "golden", being the most common prefix attached to the names of ennobled soldiers in the 17th Century.

For the next couple of centuries, the Gyllenhaals would provide many of Sweden's finest soldiers, farmers and scientists. At their Holberg estate in the Norra Vanga parish of Vestergotland they'd experiment with crops such as American maize. Leonard Gyllenhaal, born in 1752 and a leading Swedenborgian (his religion being considered by its proponents to be a step on from Christianity as Christianity was from Judaism) would become a noted entomologist, building the famous Flyhouse in his garden and writing the Insecta Suecia, a revered tome identifying thousands of Sweden's creepy-crawlies. 1837 would see Carl Hennk Gyllenhaal become the family's first baron while, 14 years later, his cousin Lars Herman, who'd been both a Cabinet Minister and Prime Minister for Justice, would be decorated in the Serafimer order, Sweden's highest level of knighthood, winning the Gyllenhaals their third family crest. Three crests! That's some serious heraldry they've got going there.

The man who brought the Gyllenhaals to America was Anders, born in 1842 and grandson of Leonard. After emigrating he'd seek his fortune in the lead and cotton industries before becoming a journalist for several of the American-Swedish newspapers that abounded at the time. Also a leading Swedenborgian, he'd be known as "the nobleman of the press" for his strict morality and kind conservatism. Thus began the Gyllenhaals long connection with language, politics and the American media, a connection that, some 100 years after Anders' death in 1905, at the time when Jake was being Oscar-nominated for Brokeback Mountain, would see another Anders (Jake's uncle) as managing editor of the Minneapolis Star Tribune and Stephen (Jake's father) as a noted film director and poet.

Stephen had been raised in rural Pennsylvania as a Swedenborgian and had achieved a degree in English at Trinity College, Connecticut, where he'd studied under the poet Hugh Ogden (Stephen would have his first collection of poems published in 2006). Adding further literary kudos to the family, he would meet and marry one Naomi Foner, a writer of Russian Jewish extraction who'd achieved an MA in Developmental Psychology from Columbia University. After graduation she'd spend many years in public TV, working for the Children's Television Workshop alongside Jim Henson and Frank Oz, creating short animations for the original Sesame Street and, between 1971 and 1973 becoming senior producer on The Electric Company, which introduced the world to the talents of Morgan Freeman. In this last position she'd spend two years travelling the States examining the different way people were taught to read. In 1977 she'd create the Best Of Families miniseries which gave early roles to both William Hurt and Sigourney Weaver.

Once Maggie and Jake were born, their parents' careers would really take off. Having gradually worked his way into position via After School TV Specials, Stephen would in 1985 direct Certain Fury where Irene Cara and Tatum O'Neil played two mousey types who go on the lam after they're mistaken for gun-totin' prostitutes (Peter Fonda would also appear). The next year Naomi, having written for the highly acclaimed PBS Visions series, saw her first screenplay come to fruition - Violets Are Blue, wherein Sissy Spacek and Kevin Kline attempted to rekindle a high-school love.

As their influence grew, the couple's work became ever more provocative as they considered social, medical and even spiritual questions. 1987 saw Stephen deliver The Abduction Of Kari Swenson, the true-life tale of an Olympic athlete kidnapped by mountain men wanting to breed from her. The next year he'd direct the short-lived TV series Hothouse, following staff at a mental hospital, Promised A Miracle, where Rosanna Arquette and Judge Reinhold tried to heal their diabetic son through spirituality, and Leap Of Faith where Sam Neill and Anne Archer had to face up to the realities of cancer. 1988 would also bring Naomi's greatest triumph when she won a Golden Globe and was Oscar-nominated for her screenplay for Running On Empty, where River Phoenix (also Oscar-nominated) played the son of Sixties radicals on the run. Her success would see her hired to write by Steven Spielberg and Barbra Streisand and asked by Paul Newman to adapt Glendon Swarthout's hit novel The Homesman, set in the 1850s, where a man must take back east a group of women driven mad by life on the frontier. Stephen, meanwhile, would deliver Family Of Spies, A Killing In A Small Town and Paris Trout, each of them showered with nominations and awards at the Emmys, Golden Globes or both. For his own part, Paris Trout would see Stephen win an award from the Directors Guild of America.

So this was the background of Jake Gyllenhaal's early life. Surrounded by the brilliant and the talented, his earliest memories would be of Hollywood success. Quickly he and Maggie would become competitive, the young boy acting out scenes from the likes of Raging Bull and practising mimicry to seize attention at the dinner table (he did a fine Bruce Springsteen). Many dream of success in films but believe the reality of it to be distant and strange, probably impossible. Jake, though, spent his whole life on film sets and in the company of people who'd "done it". He was given, for instance, his first driving lesson by Paul Newman, Newman screaming the car full pelt at a wall then spinning it at the last to avoid disastrous contact. "Lesson Number One," said Newman, "Don't do that". For Jake it was a question of when, not how, and his ambitions were even further fuelled by the jealousy he felt when, attending the elite Harvard-Westlake private school, he saw his sister bringing maximum intesnity and flair to her drama productions. He had himself started acting lessons very early and had already starred as Fagin in a 2nd Grade adaptation of Oliver Twist.

Keen to break into the exciting world his parents inhabited, Jake was quickly desperate to audition for parts. The mother of one of his schoolmates, an agent, agreed to help, and soon he was winning parts, all bar one of which his parents would refuse to let him take. His sole success (and it was a big one) was at age 11 to score the role of Billy Crystal's son in City Slickers.

But mom and dad couldn't hold the boy off forever. Though they'd barred him from The Mighty Ducks due to its two-month shoot, come 1993 both he and Maggie would appear in their father's A Dangerous Woman, wherein Debra Winger would play a mildly retarded woman looked after by aunt Barbara Hershey (star of several of Stephen's earlier features). The arrival of alcoholic handyman Gabriel Byrne would lead to secret affairs, shameful pregnancy and murder. That same year, Jake would win a far bigger part in Josh and S.A.M, playing the cruel stepbrother of the titular protagonists, who bullies young Josh, calls him a homo and generally acts as a catalyst for the kids to flee the nest and experience their on-the-road adventures. Jake would also pop up in a January, 1994, edition of Homicide: Life On The Street, again directed by his father. Here he'd play the son of guest star Robin Williams, a man tortured by his failure to save his murdered wife. It was all great experience, and the attention-seeking Jake would particularly enjoy the rehearsal sessions he spent with his father.

Homicide would be Jake's last screen outing for some four years. His parents demanded that he now concentrate on his studies yet, though temporarily thwarted in his chosen career, his life was far from dull. The Gyllenhaal household was continually visited by artists, writers and actors, not simply through Naomi and Stephen's professional connections but also their political ties. Naomi especially was a prime mover in Hollywood politics and was a member of America Coming Together, an action committee fronted by Hollywood left-wingers and backed by financial tycoon George Soros. The family's rambling Los Angeles home was the site of many political meetings, one of them, a benefit for Medical Aid in El Salvador, seeing Isabel Allende reading by candlelight. Such were their efforts that, in 2004, the entire family would be honoured at a dinner held by the American Civil Liberties Union, receiving a Torch of Liberty award.

Jake would spend yet more time with America's left-wing elite during the summers, when the family repaired to their holiday home on Martha's Vineyard. In his teens, Jake would spend three consecutive summers working as a lifeguard on the beach, in the evenings working as a bus-boy and sous-chef in a local restaurant. Friends and neighbours would include the great and good of high society. When Jake was 16, he and the family would be invited to a 51st birthday party for President Clinton, hosted by the recently married Ted Danson and Mary Steenburgen. Jake would here forge a close friendship with First Daughter Chelsea Clinton, his other buddies including Natalie Portman and Bryce Dallas Howard. Of course, there'd be an increasing number of connections made as his father continued his directing career, making Waterland with Jeremy Irons, Losing Isaiah (written by his wife) with Jessica Lange, Halle Berry and David Strathairn, and The Patron Saint Of Liars with Ellen Burstyn.

Inspired by his sister's continuing theatrical efforts at Harvard-Westlake, then at Columbia University (and briefly at RADA), Jake would continue pressing for film roles, but his next appearance would once more be for his father, in Homegrown. Here a small gang of marijuana farmers, including Billy Bob Thornton and Ryan Phillippe, would take over the farm when boss John Lithgow is shot, getting into scrapes with local farmers, thieving rivals and the Mafia. Jamie Lee Curtis would appear as their hippie mother figure, with Jake playing one of her sons - they'd get on so well Curtis would become his unofficial godmother.

While still at school, Jake would win his first lead role, in October Sky, directed by Joe Johnston, then on a roll after The Rocketeer, The Pagemaster and Jumanji. His career was moving fast now, but thankfully, aside from his parents, there were still those capable of keeping his feet on the ground. His school drama teacher, Ted Walch, would later recall how Jake turned up to audition for the senior year play totally unprepared and, immediately afterwards, asked directions to another audition. Appalled by the boy's lack of respect for the work necessary even in a high school production, Walch refused to cast him, and the lesson was well learned. Recognising his privileged upbringing, Gyllenhaal would from now on feel a need to suffer for his art. Part of his problem had been that he'd been taking on too much. Aside from schoolwork and auditions he'd also been singing in a reasonably successful rock band, Holeshot, who'd risen to the heights of the Roxy and the Whiskey.

October Sky would be something of a revelation. Based on Rocket Boy, the autobiography of Homer Hickam Jr, this saw Jake as a young West Virginia lad obsessed with the 1957 launch of Sputnik and, in defiance of his coal miner dad, attempting to build a rocket to help the US in the space race. Chris Cooper would play the father unable to accept that a coal miner's son wouldn't mine coal, while Laura Dern would appear as a teacher pushing her pupils to reach higher. And Jake would be outstanding as the teenage visionary, driving his team to ever greater and more ingenious efforts. The public would approve to the tune of $32 million.

Graduating from Harvard-Westlake in 1998 and leaving Holeshot (actually, after dating the drummer's girlfriend he was thrown out), Jake would follow the family's party line and enrol at Columbia University, as his mother and sister had done (Naomi's brother Eric was Professor of History there, too). Here, majoring in Eastern Religions - one of his professors was Uma Thurman's father Robert - he'd study modern poetry and English literature. However, the call of Hollywood was too strong. October Sky had shown Gyllenhaal that he could front a successful movie and he came to see this spell away from the industry as losing ground, thus he left Columbia after just two years.

His decision would prove to be wise. Many movie insiders had been taken with his performance in October Sky and he would find work relatively easy to come by, leading to three releases in 2001. The first, Donnie Darko, would instantly indicate that Gyllenhaal was a new force to be reckoned with. Here, replacing a busy Jason Schwartzman, he'd play alongside Patrick Swayze and sister Maggie as an ultra-bright high school kid visited by a giant rabbit, a most un-Harvey-like creature that saves him from death and then predicts the imminent end of the world, leading young Darko into an obsession with time travel. It sounds strange, it WAS strange, but it was immensely intriguing and entertaining, probably the finest independent movie of the year. And, though it failed to reach a sizeable audience in America it was a hit in Britain and became an immediate cult classic.

Where Donnie Darko was alienated and disturbed, Jake's next character was a charming, guileless hero from the Candide mould. This was Jimmy Livingston who, in Bubble Boy, has a defective immune system and has spent his entire life in the sterile conditions of his room. However, when his beloved neighbour Marley Shelton skips off to Niagara to marry a rough rocker, he builds himself a protective bubble-suit and takes off across country to win the hand of his darling. With a standard cast of oddball extras (horrid bikers, religious cults, circus freaks) and bizarre encounters, the film drew heavily on the early works of Tim Burton, particularly Edward Scissorhands and Pee-Wee's Big Adventure. It also boasted a coarse line of humour that had the Immune Deficiency Foundation asking the public to boycott the film. But there were some brilliant moments, as when Jimmy's mother Swoosie Kurtz attempts to dampen her son's ardour by ending a story with the line "And then Pinocchio touched the filthy whore who lived next door, and died", and Gyllenhaal himself was superb as Livingston - pure, lacking any kind of cynicism, a real Stranger in a Strange Land.

Jake's next two movies would see him in eye-catching minor roles, on both occasions playing the younger lover of a troubled female lead. First, in Lovely And Amazing, there'd be Catherine Keener, an untalented artist who, frustrated by a loveless marriage and a self-obsessed family including needy actress Emily Mortimer and headstrong mother Brenda Blethyn, takes a job at a one-hour-photo booth where she meets teenage Jake. Jake, understandably, forms a crush on her, she winds up in his room and then it all blows up into a statutory rape case. It was controversial stuff (woman as rapists?), but also very real, contemplating the pursuit of happiness - typical of the Gyllenhaal family, in fact.

Jake's next older partner would be Jennifer Aniston, making her break from Friends with The Good Girl. She'd also be trapped in a bad marriage, this time to sluggard stoner John C Reilly, and would thus be attracted to young Jake, the new check-out boy at the discount store where she works. He's moody, enraptured by The Catcher In The Rye, and they embark upon a torrid affair, having sex everywhere they can - until they're spotted by Reilly's mate Bubba, who demands an outrageous price for his silence. It was Aniston's movie, but Gyllenhaal was again outstanding as a romantic outsider racked by jealousy as he's swept up by and spat out of Aniston's turbulent life.

Lovely And Amazing and The Good Girl were both thoughtful (and profitable) indie pieces. His next effort, though, Highway, would be silly, cliched and straight to video. Set in 1994, this saw Jared Leto caught with a gangster's wife, scoring some drugs and going on the run with best buddy Jake, their aim being to attend the Seattle memorial service for dead rocker Kurt Cobain. Written by Scott Rosenberg, whose previous release had been the utterly risible Gone In 60 Seconds, it aspired to be a blast of pop culture excitement but was instead just a dopey road movie, complete with a hitch-hiking hooker (Selma Blair) and a series of wacky meetings.

Better would be Brad Silberling's 1970s-set Moonlight Mile, inspired by the 1989 murder of the director's actress girlfriend Rebecca Shaeffer. Here the murdered girl is the daughter of Dustin Hoffman and Susan Sarandon, Jake playing the bereaved fiance and living with now not-to-be in-laws. Hoffman wants Jake to join him in the family business, Sarandon wants him to remain as their son, but Jake needs to breathe, to move on from his loss, particularly once he's met Ellen Pompeo, a girl also working her way through emotional trauma. Both funny and moving, it was an intelligent exploration of grief and our ways of coping with it. Importantly, it was also a major learning experience for Gyllenhaal who gained a lot from working alongside such heavyweights as Sarandon, Holly Hunter and especially Hoffman. Hoffman would later recall how nervous Jake was as filming began, his tension making him jokey, almost disrespectful. But soon, intrigued by Hoffman's constant questions and note-taking, Gyllenhaal began to pick the great man's brains. One piece of advice would bring about his very next career move.

This was to London where Gyllenhaal would make his professional theatre debut in Kenneth Lonergan's This Is Our Youth at the Garrick. Here alongside Hayden Christensen and Anna Paquin, he'd play a decadent rich kid spending a weekend stealing, dealing and taking drugs, winning an Evening Standard award as Best Newcomer, before he and Chistensen made way for Matt Damon and Casey Affleck. 2002 would be a good year for Jake, as he'd also begin a relationship with Kirsten Dunst, the couple being introduced by his sister Maggie, who'd just worked alongside Dunst in Mona Lisa Smile. The pair would quickly become Hollywood's new young golden couple, with all the concomitant tabloid attention.

Having turned down Bertolucci's The Dreamers due to what he considered excessive nudity, Jake then found himself up for one of the industry's biggest roles. With Tobey Maguire suffering back problems, he was due to step into the lead for Spiderman II, a part that would, of course, have seen him as the screen lover of his real-life partner Dunst. Fortunately, as avoidance of such a franchise allowed him to consider worthier options, Maguire recovered and Gyllenhaal instead sated any appetite he had for blockbusters by joining the cast of Roland Emmerich's The Day After Tomorrow. Here, with LA ravaged by tornados, New York buried under snow and the UK flash-frozen, climatologist Dennis Quaid had to battle his way to the Big Apple to save his son, Jake, stranded there with a school decathlon team including his beloved Emmy Rossum. It was absurd stuff, grossly sentimental with nonsensical plot-lines, but the effects were fantastic and financial success inevitable. Not that this would have been much consolation for Jake when he was very publicly dumped by Kirsten Dunst.

Having been turned down for the caped lead in Batman Begins, Gyllenhaal would follow a very different and infinitely more courageous path by taking a starring role in Ang Lee's Brokeback Mountain (his co-star would be Heath Ledger, the pair coincidentally having both been rejected for the Ewan McGregor role in Moulin Rouge). He'd actually heard about the story back when he was 17, soon after it was written by E. Annie Proulx, but had thought it too outre to pursue. Set in 1963 Wyoming, the movie would see Gyllenhaal and Ledger as young ranchers tending sheep on the titular mountain and discovering a passion neither is keen to recognise once the job is over. As Jack Twist, though, Jake is the more open of the two and it's he who breaks away from his later marriage, sees male prostitutes in Mexico and visits the also-married Ledger, reawakening their forbidden love. Both men would be Oscar-nominated for their efforts, Gyllenhaal as Best Supporting Actor.

2005 would see two more Gyllenhaal releases, both very different from Brokeback Mountain. In Proof, based on David Auburn's Pulitzer Prize-winning play, he'd be the devoted student and assistant of maths genius Anthony Hopkins, deeply in love with Hopkins' daughter, Gwyneth Paltrow, also (possibly) a wizard with figures. When Hopkins dies, Jake scours his notebooks for one last great theory but, when he finds one, doubt is cast as to whether the author was Hopkins or Paltrow. The movie was a fine portrait of campus life and an intriguing contemplation of the line between genius and madness, with Gyllenhaal and Paltrow working well together, managing to convey their feelings as friends, lovers and mathematicians.

Jake would now move from dusty academia to a dustier desert in Jarhead, based on the book by former marine Anthony Swofford and relating his experiences before and during Operation Desert Storm. Here Jake would take the lead as a member of a team of scout-snipers, trained to the point of mania by Jamie Foxx then left bored and exhausted in the constant smoke of burning oil-wells as they are not permitted to fire upon the enemy. It was powerful stuff, viewing the bigger picture of war through Jake's relationships with Foxx, his best friend Peter Stormare (coincidentally his sister Maggie's boyfriend) and his crazy peers. Director Sam Mendes would later comment that Gyllenhaal was the "least technical" actor he'd met. He couldn't hit his marks, had to be left to do his own thing, and was intense to the point of being a pain in the arse. But he was good, very good.

2006 would see Jake in another classy production, David Fincher's Zodiac. This was based on the real-life hunt for the Zodiac killer, a serial murderer who struck in San Francisco in the late Sixties and early Seventies and, despite taunting the police with a series of letters, was never caught. Alongside Gary Oldman and Robert Downey Jr, Jake would play Robert Graysmith, a cartoonist at the San Francisco Chronicle, the paper that received the letters, who became obsessed with the case and eventually wrote several books on the subject.

We can expect much from Jake Gyllenhaal in the coming years. He will surely follow his parents further into the political arena (he's already involved with Rock The Vote and the American Civil Liberties Union). And, again like his parents, through his Nine Stories production company (its name a homage to JD Salinger's book of short stories) and his acting work, he will certainly take on projects highlighting the problems and joys of the human condition. His illustrious ancestors and his fans, the Gyllenhaalics, would expect nothing less.

Dominic Wills