Jack Le Goff, the man who defined the eventing program in the United States, died July 24 in France. He was 78.

The legendary horseman revolutionized the United States equestrian program and defined an era with medals and championships.

Mr. Le Goff’s coaching record at international championships was exemplary. His teams won medals at four consecutive Olympic Games and three consecutive World Championships. He brought some of the biggest names in the sport over the past three decades to fruition.

“He was about creating riders and horsemen,” said Derek di Grazia, who represented the United States at the 1986 World Championships and is one of the most renowned trainers and course designers today. “That was a big thing with Jack. He wanted us all to know what was going on with the training and management on a daily basis. He wanted us to be aware. That was another huge part of being with Jack—being a horseman.”

Mr. Le Goff never missed winning a medal with any of the eventing teams that he coached in his 14-year tenure in the United States.

His Olympic medals included: 1972 Munich (Germany)—team silver; 1976 Montreal (Que.)—team gold and individual gold and silver; 1980 Fontainebleau (France, Alternate Olympics)—individual silver and bronze medals; 1984 Los Angeles (Calif.)—team gold and individual silver.

His World Championship medals included: 1974 Burghley (England)—team gold and individual gold; 1978 Lexington (Ky.)—team bronze and individual gold; 1982 Luhmühlen (Germany)—team and individual bronze medals.

His Pan American Games medals included: 1975 Mexico City—team gold and individual gold and silver.

In all, Mr. Le Goff’s riders won 18 medals in eight international championships, an astounding accomplishment by which the U.S. team still measures itself. His innovative, intensive training changed the U.S. eventing program forever.

“I’d say that in my run in the sport he’s one of a very small handful of what I call genius,” said George Morris, the USEF show jumping chef d’equipe. “I first knew Jack in Rome as an accomplished competitor and later in the States. He’s a very, very learned classical horseman in his methodology and background and intellect. He’s a fantastic teacher and horse trainer. His success in the sport of eventing is unparalleled.”

Mr. Le Goff started his career with horses in a racing stable before joining the army. He graduated at the top of his class, which allowed him to enter the famed French Cadre Noir where he became one of the youngest “under-riding” masters ever. Eventually, he became a “riding master” and performed with the Cadre Noir.

He was the French National Eventing Champion in 1956 and 1964. He also placed sixth individually at the 1960 Rome Olympic Games, helping the French team win a bronze medal. He represented his country again in Tokyo four years later.

Mr. Le Goff was sent by the French army to fight in Algeria immediately following the Tokyo Olympic Games. He spent two years there and returned home to retire from the army and coach the French team. He coached his first individual gold medalist, Jean-Jacques Guyon and Pitou, at the 1968 Mexico Olympic Games under the French flag.

His prowess didn’t go unnoticed; USET President Whitney Stone appointed him coach of the USET Three-Day Squad. He then moved to the United States and started an empire.

Mr. Le Goff formed a great friendship and partnership with Neil Ayer, then president of the U.S. Combined Training Association, which resulted in the decade of the 1970s being known as “The Golden Era” of eventing. Ayer helped create the USET team facilities in Hamilton, Mass., where Mr. Le Goff trained.

Denny Emerson, who rode under Mr. Le Goff on the 1974 gold-medal World Championship team, called him the “winningest” coach. Writing in the Chronicle, Emerson noted: “Right now, and I’d bet for years to come, the Le Goff dynasty will remain the gold standard against which people will measure any other USET three-day team.”

Mr. Le Goff retired as coach of the United States Three-Day Team in 1984 and served for five years as the director of the USET Training Center.

He also served as a member of the ground jury for the 1994 World Equestrian Games in The Hague (the Netherlands), the European Championships in Pratoni, Italy, the 1996 Atlanta Olympic Games and the European Championships in Burghley, England. He was the founder of the World Cup for Eventing, was an FEI O-rated eventing judge and a USEF R-rated rated eventing judge.

In recognition of his accomplishments, Mr. Le Goff was named the 1983 American Horse Shows Association Horseman of the Year and the winner of the 2003 USEF Jimmy Williams Lifetime Achievement Award. He is also a member of the U.S. Eventing Association Hall of Fame.

“Jack had the ideal job when he came to the USA—to create a program,” said USEF President David O’Connor. “That program not only produced an unprecedented amount of medals but also set a standard that has been unequaled. He was a horseman, friend, innovator and, most of all, a mentor to so many of us that had the privilege to be educated by him.”