Rescorla's British honours included the General Service Medal (1918) with clasp Cyprus.

Rick Rescorla was born in Hayle, Cornwall, on May 27, 1939. He grew up there with his grandparents and his mother, who worked as a housekeeper and companion to the elderly. In 1943, his hometown of Hayle served as headquarters for the 175th Infantry Regiment of the U.S. 29th Infantry Division, largely composed of U.S. Soldiers from Maryland and Virginia preparing for the D-Day invasion of Normandy. Young Rescorla idolized the U.S. Soldiers and wanted to become a soldier because of them.

Rescorla left Hayle in 1956, aged 17, to join the British military. He enlisted in the British Army in 1957, training as a paratrooper with The Parachute Regiment and then serving with an intelligence unit in Cyprus during the EOKA Cypriot insurgency from 1957 to 1960. He then served as a paramilitary police inspector in the Northern Rhodesia Police (now the Zambia Police Service) from 1960 to 1963, experiences which made him a fierce anti-Communist. It was during the latter post that he met and forged a "life-altering friendship" with American soldier Daniel J. Hill, who inspired Rescorla to join the U.S. Army and fight in Vietnam in order to fight the communists. On returning to London and civilian life, he joined the Metropolitan Police Service.

His tenure at the Met was short-lived and he soon resigned and moved to the United States. He lived at a YMCA hostel in Brooklyn until he was able to enlist in the Army. "Rick", as he would thereafter be known, enlisted in the United States Army in 1963 and after basic training at Fort Dix, he attended Officer Candidate School and airborne training at Fort Benning. Upon graduating Rescorla was assigned as a platoon leader in the 2nd Battalion, 7th Cavalry Regiment, 1st Cavalry Division (Airmobile).

Rescorla was sent to Vietnam, where he served under the command of Lieutenant Colonel Hal Moore. The two participated in the 1965 Battle of Ia Drang, which Moore would later describe in a 1992 book he co-authored We Were Soldiers Once… And Young, (from which the 2002 Mel Gibson film We Were Soldiers would be adapted); Rescorla is the soldier pictured on the book jacket cover. Co-author Lieutenant Colonel Hal Moore described him as "the best platoon leader I ever saw". Rescorla's men nicknamed him "Hard Core" for his bravery in battle and revered him for his good humor and compassion towards his men. He is also mentioned in the book Baptism by Larry Gwin who also fought at Ia Drang. The fourteenth chapter of the book Rescorla's Game describes him as the "Cornish Hawk". Despite this tough image, according to his second wife and widow Susan Rescorla in her book, Touched by a Hero, music was "so central" to Rick's life that he sang to his troops in Vietnam to calm them – something he would later employ during 9/11.

Between songs, Rescorla called his wife, telling her, "Stop crying. I have to get these people out safely. If something should happen to me, I want you to know I've never been happier. You made my life." After successfully evacuating most of Morgan Stanley's 2,687 employees, he went back into the building. When one of his colleagues told him he too had to evacuate the World Trade Center, Rescorla replied, "As soon as I make sure everyone else is out". He was last seen on the 10th floor, heading upward, shortly before the South Tower collapsed at 9:59 A.M. His remains were never found. Rescorla was declared dead three weeks after the attacks.

Rick Rescorla and his first wife, Betsy, met as students at the University of Oklahoma. They married in Dallas in 1972. Dan Hill was Rescorla's best man. The Rescorlas' first child was born in South Carolina in 1976 and their second 1978, while they lived in Chicago. The family moved to New Jersey.

Rescorla left teaching for higher-paying jobs in corporate security, joining Dean Witter Reynolds at their offices at the World Trade Center in New York City in 1985, and living in New Jersey. After the 1988 bombing of Pan Am FLIGHT 103 over Lockerbie, Scotland, Rescorla worried about a terrorist attack on the World Trade Center. Because his old American friend from Rhodesia, Daniel Hill, was trained in counterterrorism, in 1990 Rescorla asked him to visit the World Trade Center to assess its security. When Rescorla asked Hill how he would attack the building were he a terrorist, Hill asked to see the basement, and after the two walked down to the basement parking garage without being stopped by any visible security, Hill pointed to an easily accessible load-bearing column, and said, "This is a soft touch. I’d drive a truck full of explosives in here, walk out, and light it off." That year, Rescorla and Hill wrote a report to the Port Authority of New York and New Jersey, which owns the site, insisting on the need for more security in the parking garage. Their recommendations, which would have been expensive to implement, were ignored, according to James B. Stewart's biography of Rescorla, Heart of a Soldier.

Rescorla was uncomfortable about being portrayed as a war hero. Although he had given some interviews to his Vietnam commander, Harold Moore, for his 1992 book, We Were Soldiers Once… And Young, Rescorla chose not to read it when he saw that its cover featured a combat photograph of him. When he learned that the book was being made into a film starring Mel Gibson, he told his wife, Susan that he had no intention of seeing it, as he felt uncomfortable with anything that portrayed him or other survivors as war heroes, commenting, "The real heroes are dead".

Following the 1993 World Trade Center bombing, Rescorla invited Hill to New York, where he hired him as a security consultant in order to analyze the building's security. Although no arrests had yet been made in the case, Rescorla suspected that the bomb had been planted by Muslims, probably Palestinians, or that an Iraqi colonel of Engineers might have orchestrated the attack. Hill let his beard grow and visited several mosques in New Jersey, showing up for morning prayers at dawn. He took on the character of an anti-American Muslim, speaking fluent Arabic, in order to infiltrate and interview the other visitors to the mosques. He concluded that the attack was likely planned by a radical imam at a mosque in New York or New Jersey. Followers of Sheikh Omar Abdel Rahman, a radical Muslim cleric based in Brooklyn, were subsequently convicted of the bombing.

In 1994, Rescorla was diagnosed with prostate cancer and underwent surgery to remove his prostate. Initially, the prognosis was positive, but by 1998 the cancer had spread to his bone marrow. He underwent treatment, which involved painful injections directly into his stomach every month, and pills that dehydrated him and caused his body to swell. He also employed traditional Chinese Medicine and meditation.

After Dean Witter merged with Morgan Stanley in 1997, the company eventually occupied twenty-two floors in the South Tower, and several floors in a building nearby. Rescorla's office was on the forty-fourth floor of the South Tower. Feeling that the authorities lost legitimacy after they failed to respond to his 1990 warnings, he concluded that employees of Morgan Stanley, which was the largest tenant in the World Trade Center, could not rely on first responders in an emergency, and needed to empower themselves through surprise fire drills, in which he trained employees to meet in the hallway between stairwells and go down the stairs, two by two, to the 44th floor. Rescorla's strict approach to these drills put him into conflict with some high-powered executives who resented the interruption to their daily activities, but he nonetheless insisted that these rehearsals were necessary to train the employees in the event of an actual emergency. He timed employees with a stopwatch when they moved too slowly and lectured them on fire emergency basics.

Rescorla met his second wife, Susan Greer, an assistant to a dean at Fairleigh Dickinson University and twice-divorced mother of three daughters, in late July 1998 while jogging near her Morristown, New Jersey, home. Rescorla had been living in the area to be near his children after the divorce, and Susan first spoke to him to ask him why he was jogging barefoot, an activity he picked up in Rhodesia, where few natives had worn shoes, and which he had begun out of curiosity. Rescorla also mentioned to her that he was writing a play, M’kubwa Junction, which was set in Rhodesia, and based on his time there. The two moved into a Morristown townhouse together that October and married on February 20, 1999 in St. Augustine, Florida, where Hill, who had lived there since 1975, would again serve as best man. Rescorla chose St. Augustine because he wanted to be married somewhere near the sea, to remind him of his homeland of Cornwall. They later honeymooned in Hayle, Cornwall, in May 2000. During this time Rescorla exhibited a positive outlook about his cancer.

At 8:46 a.m. on the morning of September 11, 2001, American Airlines FLIGHT 11 struck World Trade Center Tower 1, (The North Tower). Rescorla heard the explosion and saw the tower burning from his office window in the 44th floor of World Trade Center Tower 2 (The South Tower). When a Port Authority announcement came over the P.A. system urging people to stay at their desks, Rescorla ignored the announcement, grabbed his bullhorn, walkie-talkie, and cell phone, and began systematically ordering Morgan Stanley employees to evacuate, including the 1,000 employees in WTC 5. He directed people down a stairwell from the 44th floor, continuing to calm employees after the building lurched violently following the crash of United Airlines FLIGHT 175 38 floors above into Tower 2 at 9:03 A.M. Morgan Stanley executive Bill McMahon stated that even a group of 250 people visiting the offices for a stockbroker training class knew what to do because they had been shown the nearest stairway.

Rescorla gained credibility and authority after the bombing, which resulted in a change to the culture of Morgan Stanley, which he believed should have moved out of the building because he continued to feel, as did Hill, that the World Trade Center was still a target for terrorists, and that the next attack could involve a plane crashing into one of the towers. He recommended to his superiors at Morgan Stanley that the company leave Manhattan office space, mentioning that labor costs were lower in New Jersey, and that the firm's employees and equipment would be safer in a proposed four-story building. However, this recommendation was not followed as the company's lease at the World Trade Center did not terminate until 2006. At Rescorla's insistence, all employees, including senior executives, then practiced emergency evacuations every three months.

"Men of Cornwall stop your dreaming, Can’t you see their spearpoints gleaming?,
See their warriors’ pennants streaming, To this battlefield.
Men of Cornwall stand ye steady, It cannot be ever said ye for the battle were not ready
Stand and never yield!"