University of Texas spokesman Nick Voinis on Wednesday confirmed Royal's death. Royal had suffered from Alzheimer's disease and recently fell at an assisted living center where he was receiving care.
Royal, who also starred as a defensive back and quarterback for the Oklahoma Sooners, didn't have a single losing season in his 23 years as a head coach at Texas, Mississippi State and Washington. During his 20 years at Texas (1957-1976), his teams boasted a 167-47-5 record - the best mark in the nation during that period. One season ended with an even record.
"It was fun," Royal told The Associated Press in 2007. "All the days I was coaching at Texas, I knew this would be my last coaching job. I knew it when I got here."
Royal was just 32 when Texas hired him. The Longhorns hadn't had a winning season since 1953, and Royal immediately turned the program around. Under Royal, Texas won 11 Southwest Conference titles, 10 Cotton Bowl championships and national championships in 1963 and 1969, going 11-0 each time. The Longhorns also won a share of the 1970 national title.
The son of a cotton farmer, Royal credited hard work and luck for his success. He had a knack for delivering pithy quotes about his team and opponents.
"Football doesn't build character, it eliminates the weak ones," was one of Royal's famous lines.
The national title season in 1969 included what was dubbed the "Game of the Century," a come-from-behind, 15-14 victory by the top-ranked Longhorns over No. 2 Arkansas to cap the regular season.
In Texas lore, it ranks as the greatest game ever played. President Nixon, an avid football fan, flew in by helicopter to watch. Afterward, Nixon greeted Royal with a plaque proclaiming Texas the national champion.
The Longhorns also were named national champions by United Press International in 1970, a year in which Texas lost its final game to Notre Dame in the Cotton Bowl and finished 10-1.
Royal and assistant Emory Ballard changed the football landscape with the development of the wishbone in 1968, which features a fullback lined up two yards behind the quarterback and a step in front of two other backs.
It almost didn't work. After a tie and loss in the first two games that season, a frustrated Royal inserted backup quarterback James Street to take over.
"We were struggling," Street said in 2007. "Coach Royal grabbed me and he looked for a minute as if he were having second thoughts about putting me in. Then he looked me straight in the eye and said, 'Hell, you can't do any worse. Get in there.'"
Texas won its next 30 games. Soon, rival Oklahoma and other schools started using the wishbone as well.
Royal faced criticism over the lack of black players on his first 13 Texas teams, although he had coached black players at Washington and in the Canadian football league.
At the 1960 Cotton Bowl, Syracuse accused Texas of hurling racial barbs at Syracuse's black players, which Royal denied. Texas became the first SWC school to announce it would fully integrate the athletic program in 1963, but the football program didn't have a black letterman until Julius Whittier in 1970.
Royal, who acknowledged being unconcerned about racial discrimination for much of his life, credited former President Lyndon B. Johnson with turning around his viewpoint. Johnson, who attended Texas football games after his presidency ended, was close friends with Royal.
"I'm not a football fan," Johnson once said. "But I am a fan of people, and I am a Darrell Royal fan because he is the rarest of human beings."
Royal's program faced other criticism as well.
In 1972, former Texas lineman George Shaw published "Meat on the Hoof," a searing critique of the Texas program that accused the coaches of having a class system within the program and of devising sadistic drills to drive off unwanted players.
"I want to be remembered as a winning coach, but also as an honest and ethical coach," Royal said in 1975.
Royal was among the first football coaches in the nation to hire an academic counselor to ensure athletes went on to graduate. He also set aside a fund for a special "T'' ring, which he awarded to his players upon their graduation.
When Royal inherited the Texas football program, it was in such disrepair that Memorial Stadium was surrounded by barbed wire and a chain-link fence with tall grass growing around it.
"I was disappointed," Royal said of his first impression of Texas. "But I felt I could get changes made."
The biggest victory that first season came against Paul "Bear" Bryant's No. 4 Texas A&M Aggies, clinching the Longhorns' first winning season since 1953. Texas went on to have 19 consecutive winning seasons until Royal's last in 1976, when the Longhorns finished 5-5-1.
Royal's last game was a 29-12 victory over rival Arkansas. Afterward, he and Razorbacks coach Frank Broyles announced they were retiring.
Royal also served as Texas athletic director from 1962-1979. He later became a special assistant for athletic programs to the UT president and was influential in the hiring of Mack Brown as football coach in 1997.
Texas honored Royal in 1996 by renaming the football stadium Darrell K Royal-Memorial Stadium. K was his middle name, not an abbriviation.
Royal, the youngest of six children born to Katy and B.R. "Burley" Royal, grew up in tiny Hollis, Okla., where he chopped cotton as a young boy to help his family through the Depression. His mother died before he was 6 months old, and he lost two sisters to a fever epidemic.
In 1938, Royal's father took the family from the Dustbowl to California to look for work. Homesick for Oklahoma, Royal soon packed his bags and hitchhiked his way back.