He had more victories than any other coach in the league and the only perfect season in its history, all while helping to shape pro football’s modern era.

Don Shula, who won more games than any head coach in National Football League history, led the Miami Dolphins to the league’s only perfect season and helped usher pro football into its modern era, died on Monday in Florida. He was 90.

His death, at his home in Indian Creek, near Miami Beach, was announced by the Miami Dolphins on Twitter.

Shula,a steely tactician and taskmaster, built fearsome defenses and explosive offenses in taking his teams, the Baltimore Colts and the Dolphins, to six Super Bowls. He won two with the Dolphins, crowning the 1972 and 1973 seasons.

The 1972 campaign was historic: The Dolphins won all 14 regular-season games despite losing their star quarterback, Bob Griese, to an injury in the fifth game. With the top-ranked offense and defense, they went on to win the three playoff games and capture Super Bowl VII, an unmatched string of victories.

“You were now the coach that won the big one, and that changed everything in my coaching career,” Shula said.

Shula’s career embodied the transition from an era of grind-it-out football to the high-flying modern one of glitzy entertainment and glamour. Unafraid to experiment, Shula helped introduce the pass-centric offenses that are standard today. His teams were perennial contenders and a mainstay on prime time television, which turned the N.F.L. into the nation’s richest league.

His undefeated season came just three years after the merger of the old N.F.L. and the upstart American Football League, and with the Dolphin’s Super Bowl victory over the Washington Redskins at the Los Angeles Memorial Coliseum, the league’s transformation into America’s new national pastime was all but complete.

With his perfect season Shula vanquished the ignominy of losing to Joe Namath and the New York Jets in Super Bowl III — one of the biggest upsets in professional sports — just three years earlier, when Shula coached the heavily favored Baltimore Colts. The game, at the Orange Bowl in Miami, gave the A.F.L. the legitimacy it craved while saddling Shula with the label of a coach unable to win on the biggest stage. It also signaled the victory of a flashier kind of football, led by an irrepressible Broadway Joe, over Shula’s blue-collar brand.

A year after that defeat, the Dolphins lured him away from the Colts, though the success he would go on to enjoy in Miami seemed improbable at the time. After entering the old American Football League in 1966, the Dolphins had won just 15 games in their first four seasons and just three games the year before Shula arrived.

But he took to building an even more efficient football juggernaut. With a jutting jaw and stiff spine, he had a fierce look, whether pacing the practice field, demanding that his players be prepared, or exhorting his teams from the sidelines, driving them to victory after victory.

Few coaches in any sport could match his success.

In his 33 years as a head coach, seven with the Baltimore Colts (1963-69) and 26 with the Dolphins (1970-95), his teams won 328 regular-season games — still an N.F.L. record — lost 156 and tied 6. He still holds the N.F.L. records for games coached (526) and total victories (347 — 23 more than the legendary George Halas of the Chicago Bears). His teams won 10 or more games in a season 21 times and reached the playoffs 19 times. He was coach of the year three times with the Colts.

Marv Levy, who coached the Buffalo Bills to four Super Bowls, called Shula “the greatest coach in professional football history.”

Shula, who entered the Pro Football Hall of Fame in 1997, was a longtime member of the N.F.L.’s influential competition committee, which pushed to tighten rules against a defense’s holding wide receivers; with receivers freer to maneuver, the rule change tilted the advantage to the offense, paving the way for more risk-taking, high-scoring contests dominated by the passing game.

Shula coached three Hall of Fame quarterbacks: Johnny Unitas at Baltimore and Bob Griese and Dan Marino at Miami. He fathered two coaches: His son Dave was head coach of the Cincinnati Bengals for parts of five seasons, and his son Mike was head coach at the University of Alabama and has been a position coach with several N.F.L. teams, currently the Denver Broncos.

Don Shula became a head coach at 33, Dave at 32 and Mike at 37.

Shula was famous for working players hard during training camp, holding four workouts a day in South Florida’s steamy summers. During his early years on the sideline, he was known to be short-tempered and quick to blame players when things went badly.

“As a younger coach, I was very intense,” he told the columnist Dave Anderson of The New York Times in 1983. “Sometimes I was less than understanding. I hope I have been able to balance it out a little, but I also hope that I never give up being intense.”

By the Dolphins’ unbeaten season in 1972, Shula’s players had found a way to ease the tension.

About a week before the Super Bowl, defensive linemen Bill Stanfill and Manny Fernandez, both fun-loving characters, went fishing and caught and captured a three-foot alligator. After practice the next day, running back Larry Csonka distracted Shula’s secretary so that Fernandez could leave the alligator in Shula’s private shower. When the coach stepped in, he found the alligator, screamed and ran into the locker room to confront his players.

“I said, ‘I don’t think that’s very funny,’” Shula said, recounting the story in an interview with The New York Times in 2016. “They said, ‘Coach, can’t you take a joke?,’ and I said, ‘A joke? A live alligator?’ They said, ‘We took a vote and you only passed by one vote on whether we should tape up the mouth of the alligator.’”

Linebacker Nick Buoniconti said Shula started laughing and the team soon joined in. “It really loosened everybody up,” Buoniconti said.

The Dolphins went on to beat the Washington Redskins, 14-7, to win their first Super Bowl and finish the season 17-0.

Shula’s arrival in Miami did not start out smoothly. He was under contract with Baltimore when the Dolphins’ owner, Joe Robbie, signed him, so the Colts filed a tampering charge with the N.F.L. The Dolphins were forced to give up their first-round draft pick in 1971 as compensation. (The Colts picked the University of North Carolina running back Don McCauley, who played 11 seasons with them.)

“Then things changed drastically for the better,” Csonka once told an interviewer.

In his first year in Miami, Shula used an offensive line stocked with future Hall of Fame players like Larry Little and Jim Langer to block for Csonka and his fellow running backs Jim Kiick and Mercury Morris. Wide receiver Paul Warfield and tight end Marv Fleming, who had won league championships elsewhere, also arrived, giving Griese fresh targets. The core of what became known as the “No Name Defense” began to shut down opposing offenses.

The team’s success turned Shula into a hero in Miami. In the early 1980s, a sign in the Orange Bowl, then the Dolphins’ home field, read: “Shula is god.” The Times sportswriter Larry Dorman wrote “About the only argument it ever generated around town concerned whether the letter ‘g’ should be upper or lowercase.”

A road in Miami is named Don Shula Expressway. At John Carroll University near Cleveland, his alma mater, football is played in the Don Shula Stadium, and other sports events are held at the Don Shula Sports Center.

Donald Francis Shula was born on Jan. 4, 1930, in Grand River, Ohio, about 40 miles east of Cleveland. He was a running back at John Carroll and earned a bachelor’s degree in sociology there with a minor in mathematics in 1951. He received a master’s in physical education at Western Reserve (now Case Western Reserve) in 1954.

In 1951, the Cleveland Browns drafted him in the ninth round and gave him a $5,000 salary. From 1951 to 1957 he played defensive back for the Browns, under the longtime coach Paul Brown, as well as the Colts and the Redskins. He ended his career with 21 interceptions.

Shula was an assistant coach at Virginia in 1958, an assistant at Kentucky in 1959 and defensive coordinator of the Detroit Lions from 1960 to 1962 before taking over in Baltimore. Despite their success under Shula, the Colts lost Super Bowl III to the New York Jets, who were heavy underdogs, 16-7.

His move to Miami was sweetened by a 10 percent share of ownership, which he sold back to the team a few years later.

Shula’s run of three straight Super Bowls ended in 1974, when Csonka, Kiick and Warfield left for the upstart World Football League. The Dolphins returned to playoffs regularly afterward, and appeared in two Super Bowls in the 1980s, although they lost both. Despite Marino and one of the league’s most prolific offenses, the dynamic success of those early years never returned.

By 1995 Shula’s Dolphins had a leaky defense and barely made the playoffs that year, with a 9-7 record; they were eliminated in the first round when they lost a wild-card game. Players openly criticized coaches. One pro coach, Mike Ditka, called the Dolphins “a team without heart”; another, Ron Meyer, said, “Shula has lost control of his team.”

Shula resigned after that season, the day after he turned 66.

“I’m sad that he was driven out by all the criticism, a lot of it totally uncalled-for,” Fernandez, his former defensive tackle, told The Times. “But I’m happy for him that it’s over. He doesn’t have to put up with all this anymore.”

After football, Shula played golf, owned a hotel and golf club, ran a chain of steakhouses bearing his name and made speaking and charity appearances.

His first wife, the former Dorothy Bartish, died in 1991 after 32 years of marriage. He married Mary Anne Stephens in 1993. Along with her and David and Michael, his survivors include three daughters, Donna, Sharon and Annie; and three stepchildren, John Smith, Jimmy Stephens and Carrie LaNoce; 16 grandchildren and five great-grandchildren; his sisters Jennette and Irene, and a brother, Jim.

Shula was not happy to stop coaching. “The toughest part will be in September,” he said after retiring, “when that ball is kicked off, and for the first time in 43 years I won’t be on the sidelines. That is what I will miss most.”