John Madden, the Hall of Fame coach who became one of America’s most recognizable ambassadors of professional football, reaching millions, and generations, from the broadcast booth and the popular video game that bears his name, died on Tuesday. He was 85.

The National Football League announced his death in a statement that didn’t include the cause.

In his irrepressible way, and with his distinctive voice, Madden left an imprint on the sport on par with titans like George Halas, Paul Brown and his coaching idol, Vince Lombardi. Madden’s influence, steeped in Everyman sensibilities and studded with wild gesticulations and paroxysms of onomatopoeia — wham! doink! whoosh! — made the N.F.L. more interesting, more relevant and more fun, for over 40 years.

“John Madden is as important as anybody in the history of football,” Al Michaels, his broadcast partner from 2002 through 2008 with ABC and NBC, said in an interview in 2013. “Tell me somebody who did all of the things that John did, and did them over this long a period of time.”

Madden retired from coaching the Oakland Raiders in 1979, at age 42 and with a Super Bowl victory to his credit, but he turned the second act of his life into an encore, a Rabelaisian emissary sent from the corner bar to demystify the mysteries of football for the common fan and, in the process, revolutionize sports broadcasting.

Rising to prominence in an era of football commentating that hewed mostly toward a conservative, fairly straightforward approach, Madden’s accessible parsing of X’s and O’s added nuance and depth, and also a degree of sophistication that delighted an audience that in some cases tuned in just for him.

Fastidious in his preparation, Madden introduced what is now a standard exercise in the craft — observing practices, studying game film and interviewing coaches and players on Fridays and Saturdays. Come Sundays, he would distill that information into bursts of animated, cogent and often prescient analysis, diagraming plays with a Telestrator, an electronic stylus (whose scribbles and squiggles reflected its handler’s often rumpled appearance) that showed why which players went where.

Madden spent his first 15 years at broadcasting at CBS, starting in 1979. There he introduced his Thanksgiving tradition of bestowing a turducken — a turkey stuffed with duck stuffed with chicken — to the winning team. But the three other major networks all came to employ him because, at one point or another, they all needed him.

Fox snagged him in the mid-1990s to establish credibility for its fledgling sports division. ABC followed in 2002, to boost the sagging fortunes of “Monday Night Football.” NBC hired him when it regained football in 2006 — because, as Dick Ebersol, then the chairman of NBC Universal Sports, said: “He’s the best analyst in the history of sports. He’s able to cut through from people my age, who remembered him as a coach, all the way to 12-year-olds.”

Madden received 16 Sports Emmy Awards, including 15 for top analyst.

He parlayed his appeal into a series of career incarnations — commercial pitchman, successful author, video-game entrepreneur — and embraced them all with zest. He produced three New York Times best-sellers. He peddled “Boom! Tough Actin’” Tinactin as an athlete’s foot remedy and broke through reams of paper (and the odd door) in advertisements for Miller Lite. His Electronic Arts video game evolved into a cultural phenomenon with annual midnight releases and widespread tournaments after its inception in 1988, selling tens of millions of copies with revenue in the billions.

At his core, though, Madden was a coach and by extension a teacher; as he proudly noted in interviews, he graduated with a master’s degree in physical education, a few credits sort of a doctorate, from California Polytechnic State University, San Luis Obispo. His unscripted style translated as well in the Raiders’ locker room, where he guided a cast of self-styled outlaws and misfits to eight playoff appearances in 10 seasons as head coach, as it did in living rooms, man caves and bookstores.

“He was who you saw on TV,” said Ted Hendricks, a Hall of Fame linebacker who played for Madden from 1975 through 1978. “He gave us freedom, but he always had complete control of his players.”

As inclusive as he was beloved, Madden embodied a rare breed of sports personality. He could relate to the plumber in Pennsylvania or the custodian in Kentucky — or the cameramen on his broadcast crew — because he viewed himself, at bottom, as an ordinary guy who just happened to know a lot about football. Grounded by an incapacitating fear of flying, he met many of his fans while crisscrossing the country, first in Amtrak trains and then in his Madden Cruiser, a decked-out motor coach that was a rare luxurious concession for a man whose idea of a big night out, as detailed in his book “One Size Doesn’t Fit All” (1988) was wearing “a sweatsuit and sneakers to a real Mexican restaurant for nachos and a chile Colorado.”

For more than 20 years, that bus shepherded Madden to and from his assignments, a fulfillment of sorts of a favorite book, “Travels with Charley,” by John Steinbeck, who had driven around America in a camper with his poodle. When Madden greeted family and friends on the flight he chartered for them to attend his induction ceremony into the Pro Football Hall of Fame in Canton, Ohio, in August 2006, it was his first time in an airplane in 27 years.

“When you pulled up somewhere in that bus, it was like Air Force One had arrived,” said Fred Gaudelli, who as Madden’s producer at ABC and NBC traveled with him for seven years. “It was amazing the way people would react to that thing.”

If contemporaries like Bud Grant and Tom Landry epitomized the archetype of coach as sideline stoic, Madden served as their counterweight. He imparted an iconoclastic, demonstrative presence, one that echoed the spirit of the 1970s and the countercultural nexus of Northern California and that also suited his team of so-called renegades. The enduring image of Madden was of his oversize frame bounding onto the field, flouting the tenets of sideline decorum with arms flailing, mouth racing and red hair flopping against a pink face.

Madden ditched the dress code and encouraged individual expression, tolerating his players’ penchant for wild nights and carousing because, he knew, they would always give him their full effort — especially on Sundays. Unlike the disciplinarians of his day, he imposed few rules, asking them only to listen, to be on time and to play hard when he demanded it. Madden told The New York Times in 1969 that “there has to be an honesty that you be yourself”; for him, that meant treating his players as “intelligent human beings.”

Madden, at age 32, inherited a team in 1969 that had gone a combined 25-3 the previous two seasons, and he maintained the Raiders’ standard of excellence. Perhaps his greatest accomplishment was working as long as 12 years for Al Davis, the Raiders’ irascible and Machiavellian owner — and staying close friends until Davis’s death in 2011.

But when Madden retired, having been pummeled by ulcers and panic attacks and what is now regarded as burnout, he could boast of a résumé that included a Super Bowl XI demolition of Minnesota in 1977; a .759 regular-season winning percentage (103-32-7), best among coaches who have worked at least 100 games; and an on-field view of some of the most controversial and memorable games in football history: the notorious “Heidi” game (1968), the Immaculate Reception (1972) and the infamous Holy Roller play in 1978, his final season.

The thought of overseeing another minicamp, another round of draft-preparation, bedeviled him. Lombardi coached for 10 years, and so would Madden.

“You traveled around but you never saw anything,” Madden told The Washington Post in 1984. “Everything was an airplane, a bus, a hotel, a stadium, a bus, an airplane and back home. One day I said, ‘There has to be more to life than this.’”

Bam.

And there was.