Assange has described himself to collaborators, only partly in jest, as "somewhere on the autistic spectrum."
Assange guards his privacy so ferociously that when he turned himself in to British police in connection with the Swedish sex case, he refused to be fingerprinted, photographed or swabbed for a DNA sample. Once in court, he refused to tell the judge his address, offering first a post-office box and then an Australian address where he lived several years ago. The "red notice" sent out by the international law enforcement group Interpol, which came after Swedish authorities issued their European warrant for his arrest, listed Assange's age as 39, and his place of birth as Townsville, Australia.
According to press reports, including an in-depth profile published in the New Yorker magazine in June, shortly before WikiLeaks' first dump of Pentagon files, Assange's early life and family background were almost as turbulent as the recent events surrounding him.
Published accounts - including stories cited by Assange's lengthy entry in the online data bank Wikipedia - say that when he was one year old, his mother married a theatre director, with whom she collaborated on touring productions. At one point the family lived on a rock outcropping known as Magnetic Island, where, according to the New Yorker, their house burned down.
The magazine says that when Assange was eight years old, his mother left his father and took up with a musician, with whom she had another child. That relationship then soured, causing a bitter custody fight over Assange's half-brother. In turn, Assange's mother took up an itinerant existence in an effort to avoid the ex-boyfriend, who Assange told the New Yorker may have belonged to a sinister cult known as "The Family." By the time he was 14, Julian and his mother had moved 37 times. For education, Julian was partly home-schooled, but also heavily self-taught.
"I spent a lot of time in libraries going from one thing to another, looking closely at the books I found in citations," he told the magazine.
At some point in his early teens, according to the New Yorker's account, Assange's mother rented a house across the street from an electronics shop. Assange wrote his first programs on a primitive Commodore 64 and was immediately hooked by the wonders of technology.
Later, he acquired a modem, which enabled him to plug into primitive computer networks. This in turn introduced him to the world of computer hacking, a pastime he is reported to have embraced with gusto.
Using the nickname "Mendax" - a classical Latin word for "liar" - Assange joined two other fledgling hackers to form a posse which called itself the "International Subversives." The group launched forays into the computer systems of some of America's most sensitive government installations, including nuclear weapon labs.
But according to a book about the budding hacker subculture called "Underground," for which Assange served as Australian author Suelette Dreyfus' researcher, he and his pals tried to operate by what in hindsight sound like a notably benign set of self-imposed guidelines: Don't damage or crash networks you hack into; don't mess with the data and share information.
Before he was out of his teens, Assange's involvement in the hacker subculture involved him in clashes with authority. At one point, Australian police raided his residence and confiscated his computer gear, though they later gave it back. In the early 1990s, Australian federal authorities launched a major investigation into the International Subversives, which, according to an account offered in the book he researched, fueled Assange's own growing paranoia. "Mendax dreamed of police raids all the time. He dreamed of footsteps crunching on the driveway gravel, of shadows in the pre-dawn darkness, of a gun-toting police squad bursting through his backdoor at 5 am."
According to the New Yorker, Assange became so strung out waiting for the knock on the door that his teenage sweetheart, whom he had married, found his behavior so intolerable that she moved out, taking with her their young son. He subsequently became embroiled in a bitter child custody fight with the child's mother; Assange's mother told the magazine this inculcated in her son a deep antipathy to bureaucracy which he believed was "squashing people." She and Julian even launched an organization to campaign against local child protection authorities.