Giuliani was born in an Italian-American enclave in East Flatbush in the New York City borough of Brooklyn, the only child of working-class parents, Harold Angelo Giuliani (1908-1981) and Helen Giuliani (nee D'Avanzo; 1909-2002), both children of Italian immigrants. Giuliani is of Tuscan origins from his father side, as his paternal grandparents (Rodolfo and Evangelina Giuliani) were born in Montecatini, Tuscany, Italy. He was raised a Roman Catholic. Harold Giuliani, a plumber and a bartender, had trouble holding a job, and was convicted of felony assault and robbery, serving time in Sing Sing.

For his leadership on and after September 11, Giuliani was given an honorary knighthood (KBE) by Queen Elizabeth II on February 13, 2002.  Giuliani initially downplayed the health effects arising from the September 11 attacks in the Financial District and lower Manhattan areas in the vicinity of the World Trade Center site. He moved quickly to reopen Wall Street, and it was reopened on September 17. In the first month after the attacks, he said "The air quality is safe and acceptable." However, in the weeks after the attacks, the United States Geological Survey identified hundreds of asbestos 'hot spots' of debris dust that remained on buildings. By the end of the month the USGS reported that the toxicity of the debris was akin to that of drain cleaner. It would eventually be determined that a wide swath of lower Manhattan and Brooklyn had been heavily contaminated by highly caustic and toxic materials. The city's health agencies, such as the Department of Environmental Protection, did not supervise or issue guidelines for the testing and cleanup of private buildings. Instead, the city left this responsibility to building owners.  Giuliani took control away from agencies such as the Federal Emergency Management Agency, the Army Corps of Engineers and the Occupational Safety and Health Administration, leaving the "largely unknown" city Department of Design and Construction in charge of recovery and cleanup. Documents indicate that the Giuliani administration never enforced federal requirements requiring the wearing of respirators. Concurrently, the administration threatened companies with dismissal if cleanup work slowed. In June 2007, Christie Todd Whitman, former Republican Governor of New Jersey and director of the Environmental Protection Agency (EPA), reportedly stated that the EPA had pushed for workers at the WTC site to wear respirators but that she had been blocked by Giuliani. She stated that she believed that the subsequent lung disease and deaths suffered by WTC responders were a result of these actions. However, former deputy mayor Joe Lhota, then with the Giuliani campaign, replied, "All workers at Ground Zero were instructed repeatedly to wear their respirators."  Giuliani asked the city's Congressional delegation to limit the city's liability for Ground Zero illnesses to a total of $350 million. Two years after Giuliani finished his term, FEMA appropriated $1 billion to a special insurance fund, called the World Trade Center Captive Insurance Company, to protect the city against 9/11 lawsuits.  In February 2007, the International Association of Fire Fighters issued a letter asserting that Giuliani rushed to conclude the recovery effort once gold and silver had been recovered from World Trade Center vaults and thereby prevented the remains of many victims from being recovered: "Mayor Giuliani's actions meant that fire fighters and citizens who perished would either remain buried at Ground Zero forever, with no closure for families, or be removed like garbage and deposited at the Fresh Kills Landfill", it said, adding: "Hundreds remained entombed in Ground Zero when Giuliani gave up on them." Lawyers for the International Association of Fire Fighters seek to interview Giuliani under oath as part of a federal legal action alleging that New York City negligently dumped body parts and other human remains in the Fresh Kills Landfill.

What did Giuliani do in the aftermath of 911?
Giuliani initially downplayed the health effects arising from the September 11 attacks