LOS ANGELES - Roy E. Disney, 79, the nephew of Walt Disney whose powerful behind-the-scenes influence on the Walt Disney Co. led to the departure of former chief Michael Eisner, has died.

The company announced that Mr. Disney died yesterday in Newport Beach, Calif., after a yearlong bout with stomach cancer.

Bob Iger, the company president and chief executive, said in a statement that Mr. Disney was much more than a valued 56-year company veteran.

"Roy's commitment to the art of animation was unparalleled and will always remain his personal legacy and one of his greatest contributions to Disney's past, present and future," Iger said.

Although he generally stayed out of the spotlight, Roy Disney did not hesitate to lead a successful campaign in 1984 to oust Walt Disney's son-in-law after concluding he was leading the company in the wrong direction.

Nearly 20 years later, he launched another successful shareholders revolt, this time against Eisner, the man he had helped bring in after the previous ouster.

Eisner and his wife issued a statement expressing sympathy over Mr. Disney's death.

Don Hahn, an executive producer at the Disney movie studio, credited Roy Disney with ushering in a new era after taking over the animation department in 1984. Together, they helped make such blockbusters as Beauty and the Beast and The Lion King.

"He took it under his wing, was a cheerleader, a coach, therapist," Hahn said.

Born in 1930, Roy Disney had practically grown up with the company. His uncle Walt Disney and his father, Roy O. Disney, cofounded the Disney Brothers Cartoon Studio seven years before, later renaming it the Walt Disney Co.

While Walt was the company's creative genius, his brother was the one in charge of the company's finances.

Starting in the 1950s, the younger Roy Disney worked for years in the family business as an editor, screenwriter, and producer. Two short films he worked on were nominated for Academy Awards: the 1959 "Mysteries of the Deep," which he wrote, was nominated as best live-action short, and the 2003 film "Destino," which he coproduced, was nominated as best animated short.

Despite his heritage, Roy Disney never got the chance to lead the company. But as a vice chairman of the studio, he would frequently appear at theme parks or help promote the company's animated films. He resembled his uncle so much that people in public would frequently approach him asking if he was Walt Disney's brother.

Born in Los Angeles on Jan. 10, 1930, Roy Edward Disney was Roy and Edna Disney's only child. As an adult, he bought a castle in Ireland and indulged his passion for yacht racing, setting several speed records. He was also an active philanthropist.

In 1955, he married Patty Daily. They had two sons and two daughters. The couple divorced in 2007. He is survived by his wife, Leslie DeMeuse Disney; daughters Abigail and Susan; sons Roy and Timothy; and 16 grandchildren.