But Giuliani thrived on conflict. His enemies gave him a purpose, a way to define himself, a reason to stand apart, a trait that flourished years later when he became known as a mob-busting prosecutor and the mayor who tamed the famously ungovernable New York. When they graduated from high school, Giuliani’s friends asked for cars. Rudy asked for a big desk and a high-backed leather chair. Everything he said and did seemed to aim him for bigger things.

As a baby, Giuliani was restless and prone to staying awake for 48 hours at a time. His parents endured his unrelenting energy as they did everything about him, with bottomless devotion. Harold and Helen Giuliani had tried for six years to have a baby before their one and only child was born May 28, 1944, nine days before D-day. “He was unexpected and they worshipped the ground he walked on,” his aunt, Anna D’Avanzo, who married his mother’s brother, once said. “Anything he wanted, he got.”

He was named for his paternal grandfather, Rodolfo Giuliani, a tailor, who raised his family in East Harlem after immigrating to America in the early 1900′s from Tuscany. Giuliani’s grandparents on his mother’s side settled in Brooklyn after emigrating from Naples. Until Giuliani was 15, his mother, Helen, a quiet and measured woman, stayed home full-time to dote on him and help with his school work. His father, Harold, taught his son lessons not found in most books. He encouraged young Rudy to resort to fisticuffs with anyone who picked a fight with him.

Harold Giuliani was an odd mix of bravado and frailty. He drank milk because of an ulcer and a bad heart even as he worked as a bartender in the Flatbush section of Brooklyn, where he subjected his patrons to an unceasing flow of opinions on everything from the Yankees to presidential politics. He kept a baseball bat behind the bar, and was known to use it to collect outstanding tabs. The darkest details of Harold Giuliani’s past did not fully emerge until 2000 when investigative reporter Wayne Barrett unearthed that he had been arrested in 1934 — ten years before his son’s birth — for robbing a milkman of $128.82 at gunpoint. Under the alias “Joseph Starrett,” Harold Giuliani pled guilty and spent 16 months at Sing-Sing.

Rudy had four uncles who were police officers and a fifth who was a firefighter. But Harold Giuliani was not the only family member who had ended up on the wrong side of the law. A cousin ran a stolen car ring. And Harold’s brother-in-law Leo D’Avanzo was a Brooklyn loan shark. Harold worked as Leo’s muscle, collecting as much as $15,000 a week. When customers didn’t pay up, according to Barrett, Harold was prone to reaching for the bat and breaking bones. Rudy Giuliani has never talked at length about how his familial ties to crime may have affected him as a youngster. But he has said that his father constantly pushed him to behave properly and that he may have moved him and his mother from Brooklyn to Long Island when he was a kid to help ensure that he’d avoid unsavory influences.

Young Rudy didn’t find any budding gangsters at St. Anne’s parochial school, where he prepared for his Holy Communion by studying the Baltimore Catechism. In those years before Vatican II, the Catechism taught that there was a wrong way and a right way — and that the Catholic way was right. It was a world of black-and-white rules, with few gray shades, a style of thought that Giuliani internalized and would adopt as his own. Giuliani’s immersion in Catholicism continued at Bishop Loughlin Memorial High School, which was run by a French order of Christian Brothers, who ran things with a firm hand. The school forbade students from indulging in the usual adolescent practices of the day — no ducktail haircuts, no loud ties, no smoking, no running up the stairs, no taking off sports jackets, no lateness, and no excuses. In a school of 1,825 students, virtually all of them white, Giuliani still managed to make an impression, and not only because he was the first to start an opera club. “He looked like a little man, not a student, like he was dressed to go to IBM,” one classmate, Thomas McVann, recalled.

Giuliani became friendly with two youngsters with whom he’d form long-lasting ties. One was Peter Powers, who would become his deputy mayor years later. The other was Alan Placa, who would become a monsignor and one day help him get his first marriage annulled. Placa recognized almost immediately that his new friend was unique. “He didn’t carry around a notebook like the other kids,” Placa said. “He took notes on unlined, blank paper, loose sheets. Then he’d put the sheets in file folders. He might take them out, move them around, add more notes. The notebooks gave you an order for your notes. In his system, Rudy was imposing his own order.”

As he entered his senior year in 1960, Giuliani became fascinated with the presidential campaign of John F. Kennedy, who was on his way to becoming the country’s first Catholic president. One afternoon, Giuliani convinced friends to skip classes and go to a Kennedy rally at the Garment District in Manhattan, and got close enough to shake the candidate’s hand. It was the Kennedy-Nixon debates that inspired Loughlin students to stage their own debate between the three candidates running for senior class president.

“A question for Mr. Shanley,” a student called out, rising from a creaking wooden seat to question Anthony Shanley, the Gold Party candidate, who stood on the stage with his two opponents, Joe Centrella of the Purple Party and George Schneider of the White Party.

Why, the student asked, did Shanley claim that his opponents were too busy with track and basketball to be effective if elected? In fact, the student demanded, wasn’t Shanley himself involved in student theater and a host of other extra-curricular activities? Well, wasn’t he?

Shanley squinted into the audience at his inquisitor. Who was this chubby-faced kid with the coal black eyes? Hadn’t he seen this kid pumping his fist out a car window days before, exhorting classmates to vote for George Schneider?

Shanley groaned. Of course. It was Schneider’s campaign manager, Rudy Giuliani.

Giuliani’s ambush did not affect the outcome of the election. But his taste for the jugular — a taste he would demonstrate as a prosecutor and a politician — was already making an impression. He graduated from Bishop Loughlin believing he would become a priest or even maybe a doctor. But his classmates knew better. In its senior poll, the Class of 1961 chose Rudy Giuliani as class politician.

Giuliani spent the summer after high school toying with the idea of entering the priesthood. But he changed his mind, he has said, because he believed he was incapable of living a life of celibacy. He enrolled at all-male Manhattan College, also run by the Christian Brothers, where he bared the competitive edge and resilience for which he would later become well known.

An early proving ground was his quest to join a fraternity, an essential part of the college’s social life. Giuliani, the sophomore class’s newly elected president, believed that he belonged at Alpha Sigma Beta, the frat that attracted jocks and class leaders. ASB accepted Giuliani as a pledge and subjected him to weeks of hazing, which included shining brothers’ shoes, eating raw eggs, and waddling around the campus like a duck. But the frat blackballed Giuliani after the first round, infuriating him.

Giuliani didn’t allow his dream to join a frat fade. He signed up with Phi Rho Pi, the college’s smallest and least popular frat, and eventually became its president. As a fraternity leader, he had to deal with a split within the ranks between those who were often sober and straight-laced — his constituents — and those who liked to party. In other words, what the frat brothers referred to as the Tigers and the Pussies.

“Rudy was one of the Pussies,” said Sal Scarpata, a pillar of the Tiger contingent. Giuliani often ran the meetings at which the fraternity’s two sides debated plans. “He was a little dictatorial,” said Tom Hefele. “He would tell people the way it was. The idea was: if you want to get things done, do it your way. You’re the puppeteer.” Giuliani’s leadership style enraged Scarpata, who didn’t like the way he invoked Robert’s Rules of Order to maintain control over the meetings and quash debate. Once, Scarpata hurled a bottle of Seven-Up at Giuliani’s head. They ended up at a park fighting and wrestling. Another time, Scarpata said something lewd about Giuliani’s girlfriend. Rudy went after him, only to be restrained by two classmates.

“We had to drag Rudy down because he was going to kill Sal,” recalled Tony Mauro. “Rudy was like a bear chasing after him.”

The girlfriend was Kathy Livermore, whom Giuliani met one summer while working at a savings bank in Freeport, N.Y. She was a clerk, Long Island’s answer to Julie Christie, leggy, full-lipped and blonde. They spent two years together, sharing secrets and dreams. He told her he wanted to be the first Italian elected president, and outlined ways to rise in politics, whether it was by joining the military or becoming a lawyer.

Getting into law school was easier with a resume heavy on the extra-curricular side. Giuliani devoted a portion of his spare time to writing a political column for his school newspaper. He showed off his Democratic leanings by extolling the virtues of Robert F. Kennedy, who was then running for the U.S. Senate (Giuliani would become a Republican years later), and frothing over the likes of GOP icon Barry Goldwater, whom he described as an “incompetent, confused and sometimes idiotic man.”

Giuliani tried his own hand at electoral politics, running for junior class president with Powers as his running mate. Giuliani had all the advantages, not the least of which was that he towered over his opponent, Jim Farrell, who was so small he wore a boy’s size suit. But Farrell won by more than 75 votes, frustrating Giuliani.

“His eyes looked like the fires of hell,” Bernie McElhone, a classmate, recalled. “He was enormously, gargantuanly pissed off.” The following year, Farrell ran for student council president. His opponent was Peter Powers. Again, Farrell was victorious, beating Powers by more than 200 votes. “Pete was extraordinarily gracious,” Farrell recalled years later. “He offered to do anything to help if I needed him.”

And Giuliani?

“He would show up at Student Council meetings and scowl at me.”

Farrell has run into Giuliani and Powers over the years, including at the 1994 St. Patrick’s Day luncheon, three months after Giuliani became mayor. Powers spotted Farrell and shouted, “Hey, everyone, say hello to the only guy who ever beat me and Rudy Giuliani.”

Powers encouraged Farrell to greet the mayor, who was seated at the dais. All those years later, the mayor barely resembled the cherubic young man Farrell knew at Manhattan College. Yet, in some ways, Rudy Giuliani hadn’t changed at all.

“I reached up my hand, and Giuliani looked at me like, ‘Who the fuck are you?’” Farrell recalled. Then, without uttering a word, Giuliani turned away.