John du Pont was born on November 22, 1938, in Philadelphia, Pennsylvania, the youngest of four children of William du Pont, Jr. and Jean Liseter Austin (1897–1988). He grew up at Liseter Hall, a mansion built in 1922 in Newtown Square, Pennsylvania, by his maternal grandfather on more than 80 hectares (200 acres) of land given to his parents at their wedding by his maternal grandfather. Both his parents’ families had emigrated from Europe to the United States at the beginning of the 19th century and became highly successful.

During the 1920s and 1930s, the couple acquired more land and developed Liseter Hall Farm for Thoroughbred breeding, showing, and racing. His mother retained Liseter Hall Farm after the couple divorced in 1941. She added a dairy herd of Guernseys and bred Welsh ponies at the farm. John was 2 when his parents divorced. He had two older sisters, Jean and Evelyn, an older brother Henry E. I. du Pont, and a younger half brother, William du Pont III, born of their father’s second marriage.

Du Pont graduated from Haverford School in 1957. He attended the University of Pennsylvania where he belonged to the Zeta Psi fraternity, and withdrew before completing his freshman year. Du Pont later attended college in Miami, Florida, where he studied under and was mentored by scientist Oscar T. Owre. He graduated from the University of Miami in 1965 with a Bachelor of Science degree in zoology. Du Pont went on to complete a doctorate in natural science from Villanova University in 1973.

During his graduate work, du Pont participated in several scientific expeditions to study and identify species of birds in the Philippines and South Pacific. As an ornithologist, du Pont is credited with the discovery of two dozen species of birds. He founded the Delaware Museum of Natural History in 1957. As a young man, he served on the board, helping guide the institution toward opening in 1972. After having been part of scientific expeditions, he served as director of the museum for many years.

Du Pont founded the Delaware Museum of Natural History in 1957, which opened to the public in 1972 on a site near Winterthur donated by his relative Henry Francis du Pont. John du Pont served on the board for many years. He also helped fund a new basketball arena at Villanova University, which opened in 1986. Originally it was called the John Eleuthère du Pont Pavilion, but after his conviction, his name was removed from the facility and simply called The Pavilion. Today the facility is named The Finneran Pavilion.

Du Pont was also a philatelist. Bidding anonymously in a 1980 auction, he paid $935,000 for one of the rarest stamps in the world, the British Guiana 1856 1c black on magenta. After his death, this stamp was sold at auction for $9.5 million (inclusive of buyer’s premium) at Sotheby’s June 17, 2014. For the fourth time, the stamp broke the record for a single stamp’s sale. The unique stamp was part of the estate of du Pont. According to du Pont’s will—unsuccessfully challenged by several parties—80 percent of the sale proceeds go to the family of Bulgarian wrestler Valentin Jordanov Dimitrov and 20 percent goes to the Eurasian Pacific Wildlife Foundation, based in Paoli, Pennsylvania, a group du Pont founded to support Pacific wildlife. In 1986, competing as “John Foxbridge”, he won the Grand Prix d’Honneur in the FIP Championship Class at the STOCKHOLMIA 86 international stamp exhibition for his display of “British North America”. While du Pont continued to buy stamps while in prison, he was not allowed to bring them there.

At the age of 45, on September 3, 1983, du Pont married 29-year-old Gale Wenk, an occupational therapist. They met after he injured his hand in an auto accident. They lived together for less than six months. Du Pont filed for divorce when they had been married for ten months. Wenk sued du Pont for $5 million, claiming he had pointed a gun at her and tried to push her into a fireplace. The divorce became final in 1987. Du Pont’s will excluded her from inheriting any of his estate. In 1987, it was estimated that John du Pont was worth $200 million.

Du Pont had been worth an estimated US$200 million in 1986, about $470 million in current dollars. His will bequeathed 80 percent of his estate to Bulgarian wrestler Valentin Yordanov, an Olympic champion who had trained at Foxcatcher, and Yordanov’s relatives. In June 2011, du Pont’s niece Beverly A. du Pont Gauggel and nephew William H. du Pont filed a petition to challenge the will in Media, Pennsylvania, asserting that du Pont was not “of sound mind” when he made his will. The petition claims that during that period, John du Pont asserted alternately that he was Jesus Christ, the Dalai Lama, and a Russian tsar.

In August 1988, a problem-plagued wrestling program he funded at Villanova was shut down after just two years. In December 1988, a lawsuit (which was settled out of court) claimed du Pont had made improper sexual advances to Villanova assistant coach Andre Metzger.

After his mother’s death in 1988, du Pont assumed stewardship of Liseter Farm and renamed it “Foxcatcher Farm” after his father’s famed Thoroughbred racing stable. John never lived in the manor house; he occupied a smaller house on the estate. Days after his mother’s death, he moved into the main house. He maintained much of her work, but added a wrestling facility and supporting buildings for that interest.

Du Pont became a sponsor in wrestling, swimming, track, and the modern pentathlon. He was also involved in promoting a subset of the modern pentathlon (run, swim, shoot) as a separate event. He took up athletics and became a competitive wrestler in his 50s. His only prior wrestling experience was as a freshman in high school. He began competing again at the age of 55 in the 1992 Veteran’s World Championships in Cali, Colombia; following that in 1993 in Toronto, Ontario; in 1994 in Rome, Italy; and in 1995 in Sofia, Bulgaria.

On January 26, 1996, du Pont shot and killed Dave Schultz in the driveway of Schultz’s home on du Pont’s 800-acre (3.2 km) estate. Schultz’s wife Nancy and du Pont’s head of security Patrick Goodale were present and witnessed the crime. The security chief was sitting in the passenger seat of du Pont’s car when du Pont fired three bullets into Schultz. Police did not establish a motive. Schultz had worked with du Pont to coach the wrestling team for years.

Many people had noticed du Pont’s increasingly disruptive behavior in the months before the murder. Charles King Sr. blames du Pont’s “security consultant”, Patrick Goodale, for influencing what happened. King said, “I don’t think John could shoot someone unless he was pushed to, or was on drugs. After that guy started hanging around him, my son always said Johnny changed. He was scared of everything. He was always a little off. But I never had problems with him, and my son never had problems.” After the shooting, du Pont locked himself in his mansion for two days while he negotiated with police on the telephone. Police turned off his power and were able to capture him when he went outside to fix his heater. In September 1996, du Pont was ruled incompetent to stand trial, as experts testified that he was psychotic and could not participate in his own defense. He was committed to a mental hospital and his condition was to be reviewed by the court in three months.

Du Pont pleaded “not guilty by reason of insanity.” The insanity defense was thrown out by the court, and on February 25, 1997, a jury found him guilty of third-degree murder but mentally ill. In Pennsylvania, third-degree murder is a lesser charge than first-degree (intentional) or second-degree (a killing occurring during the perpetration of a felony), and indicates a lack of intent to kill. In Pennsylvania criminal code, “insanity” applies to someone whose “disease or defect” leaves him unable either to understand that his conduct is wrong or to conform it to the law (The M’Naghten Rule).

After his arrest, du Pont sold off the dairy herd, nearly 70 Guernseys, in the fall of 1996. He ordered all the buildings at Foxcatcher Farm to be painted a matte black. The Delaware Museum of Natural History, which du Pont formerly headed and which held the dairy farm in trust, sold that portion in January 1998 after his conviction and sentencing to prison. A 123-acre (0.50 km) segment is now occupied by the campus of the Episcopal Academy, a private independent K–12 school founded in 1785, which moved there in 2008 from split campuses located in the nearby Philadelphia Main Line communities of Merion and Devon. The 90-year-old du Pont mansion, Liseter Hall, in which du Pont was raised and had lived for 57 years, was demolished by Glenn Miller Demolition in January 2013. The mansion stood on a 400-acre (1.6 km) portion of the property that is now being developed by Toll Brothers into a “master planned community of 449 luxury homes” called “Liseter Estate.” Most of the outbuildings were torn down, though an existing 7,000-square-foot historical barn will be used as a clubhouse in the new development.

Du Pont’s attorneys filed appeals. In 2000, his case reached the U.S. Supreme Court which upheld the verdict. Du Pont was first eligible for parole on January 29, 2009; it was denied. In 2010, the 3rd Circuit U.S. appeals court in Philadelphia rejected all but one issue raised on appeal (involving his use of prescribed scopolamine before he killed Schultz), and requested written briefs. Du Pont’s maximum sentence would have ended on January 29, 2026, when he would have been 87.

Du Pont died at the age of 72 on December 9, 2010, from chronic obstructive pulmonary disease (COPD). A spokesperson for the Pennsylvania Department of Corrections said du Pont was found unresponsive in his bed at the State Correctional Institution – Laurel Highlands. He was pronounced dead at 6:55 a.m. at UPMC Somerset. He was buried in his red Foxcatcher wrestling singlet, in accordance with his will, at the Du Pont de Nemours Cemetery in Wilmington, Delaware.

That petition was dismissed, and while appealed, the Superior Court of Pennsylvania has upheld a Delaware County Orphans Court order dismissing a challenge on the will on November 19, 2012. Former Delaware County Court of Common Pleas President Judge Joseph Cronin dismissed the challenge for lack of standing, finding that because the niece and nephew were not named in two successive wills going back to 2006, they would not be harmed if the September 2010 will were deemed valid. A three-judge panel of the Superior Court affirmed that ruling on November 19, 2012.