James L. Fowler, a Korean and Vietnam war veteran who dreamed up the event that became the Marine Corps Marathon, the annual race that has drawn tens of thousands of athletes to the capital over nearly four decades, died Jan. 20 in Alexandria, Va. He was 84.

The cause was congestive heart failure, said his wife, Betsy Fowler.

The Marine Corps Marathon, which first took place in 1976, is one of the largest races of its kind and is widely known as the People’s Marathon for the open spirit in which it is conducted. It welcomes first-time marathon runners as well as experienced athletes, and participants have included servicemen and women, civilians, politicians and celebrities.

The fastest finishers receive no prize money, but all runners are afforded a majestic view of Washington and its monuments across the 26.2-mile course.

Mr. Fowler, a retired colonel in the Marine Corps reserve, was an infantry battalion commander in Vietnam, where he was wounded twice, including once in the leg.

James L. Fowler, a principal founder of the Marine Corps Marathon, died Jan. 20 at 84. (Courtesy of the Fowler family)

Following a months-long recovery, he returned to a professional life that included a position at the Marine Corps headquarters. There, his wife said, he began imagining an event that would showcase the corps and foster military-civilian relations during a time of national discord.

“After the Vietnam War, popularity of the military services declined in the eyes of many,” said Mr. Fowler, according to an online history of the marathon. “At the same time, distance running was gaining considerable positive attention.”

The word “marathon,” Mr. Fowler wrote in an Oct. 17, 1975, memo to Maj. Gen. Michael Patrick Ryan, chief of the reserve, “evokes military history and is the kind of event which the public finds in consonance with the image of the Marines.”

Ryan and others helped rally support for the event, and the marathon was scheduled for Nov. 7, 1976.

“I remember somebody asking, ‘Suppose we give this marathon and nobody comes?’ ” Mr. Fowler later told The Washington Post. “It seemed like a natural but . . . this was the first race I’d ever organized.”

The marathon drew 1,175 runners to the inaugural event and became increasingly popular throughout the years. In 2012, there were 23,515 official finishers, according to the organization.

Mr. Fowler directed the first two races, ran in the third and remained active in the event until recently. The course has changed, and motorists have come to expect the road closures and diversions to accommodate the throngs of athletes and onlookers. But a highlight remains the finish line near the Marine Corps War Memorial, the monument commonly called the Iwo Jima Memorial.

“In any pictures” of the marathon, Mr. Fowler said, “the Marine Corps presence would be there, and not too subtly.”

James Loftus Fowler was born Jan. 11, 1931, in Mineola, N.Y. He graduated in 1952 from Dartmouth College in Hanover, N.H., and then received a commission in the Marine Corps Reserve.

He served in the Korean War as a rifle platoon leader, according to his family, before pursuing a civilian career initially with the Central Intelligence Agency and later at a family furniture business in New York.

Mr. Fowler remained in the reserve, with periods of active duty, until his retirement in 1982. His decorations include two awards of the Bronze Star, two awards of the Purple Heart and the Joint Service Commendation Medal.

Mr. Fowler received a law degree from Georgetown University in 1958, a master of business administration degree from the University of Virginia in 1960, a master of laws degree from Georgetown in 1961, a master’s degree in business from Columbia Business School in 1973 and a master’s degree in history from Georgetown in 1979.

He spent the last decades of his career in business, retiring in 2005 from the Unilever company, where he had been a chief of corporate security.

Survivors include his wife of 54 years, Betsy Blackwell Fowler of Alexandria.

Mr. Fowler said that he was proud of the marathon’s success.

“It will be fun for me on Sunday to look at that and say, ‘Hey, this has kind of grown,’ ” he told The Post before the 2000 race. “I get a kick out of that.”