By ANTHONY TOMMASINI

In the mid-1970s, Beverly Sills was a ubiquitous presence on American television. I remember watching her in action on one of the several occasions when Johnny Carson asked her to be the guest host of “The Tonight Show.” Ms. Sills invited three of her gal pals as guests: the comedian Carol Burnett, the singer and television host Dinah Shore and the pop chanteuse Eydie Gorme. The four women got into a tiff over who was whose best friend.

Watching Ms. Sills schmoozing with her friends on television, hearing her sing comic duets with Ms. Burnett one moment and lyrical Donizetti arias the next, had a major impact on American culture. Millions of viewers who had assumed that opera was an elitist art form for bloated divas pretending to be lovesick adolescents experienced little epiphanies before their television sets. In her day, Ms. Sills was not just the best-known, best-loved and highest-paid opera singer in the business. She was the public face of opera, and the performing arts in general, throughout America.

Yet as we remember Ms. Sills, who died on Monday night at 78, we must be careful not to dwell too much on Sills the media force. She would not have had such authority as a proselytizer for the fine arts had she not been an excellent singer and formidable artist. Sadly, her time at the top was relatively brief.

Of course, she started in the business early. Look her up on YouTube and you can find a link showing Bubbles Silverman as a 7-year-old radio darling, singing an Italian song by Luigi Arditi in a short segment from a movie titled “Uncle Sol Solves It.” Already present are hints of the coloratura agility and the communicative energy that later generations of opera buffs associate with Beverly Sills. Photos and recordings also exist of Bubbles singing a commercial jingle for Rinso White soap on Major Bowes’s radio show.

But in her early 20s she struggled, even spending a couple of years in a touring company where one season she sang 63 consecutive one-night stands as Micaela in “Carmen.” After finally being invited to join the New York City Opera in 1955, Ms. Sills spent the next 10 years giving what many company insiders thought were some of the greatest performances of her career. But only City Opera loyalists heard her.

Her breakthrough into international stardom did not come until 1966, with her portrayal of Cleopatra in the City Opera’s landmark production of Handel’s “Giulio Cesare.” Just 14 years later, at only 51, she retired from singing.

I was one of those who did not hear her during that first decade with the City Opera. But in the 1970s she came every season to Boston, where I was pursuing doctoral studies in music and later had a college teaching job. Ms. Sills was a close colleague and devoted friend of Sarah Caldwell, the founding director of the Opera Company of Boston, in those days a scrappy, chaotic yet inventive institution. Perpetually disheveled and disorganized, Ms. Caldwell both conducted and directed most productions. Still, she and Ms. Sills inspired each other.

To Ms. Sills’s mind, there were some misfires along the way, notably her participation in the United States premiere of Luigi Nono’s 12-tone opera “Intolleranza” in 1965. In her blunt 1987 memoir, “Beverly: An Autobiography,” Ms. Sills explained that she thought the composer, an avowed communist, was a hypocrite for making lavish use of the services of the Copley Plaza Hotel during his Boston stay. “All that might have been overlooked,” she wrote, “if ‘Intolleranza’ hadn’t been such a sophomoric piece of polemical garbage,” adding, “Luigi and his opera were both Nono’s.”

But I had some unforgettable experiences in Boston thanks to these two great women of opera. There was a delightful production of Rossini’s “Barbiere di Siviglia,” with Ms. Sills as a slightly ditsy Rosina, and also her vivacious yet subtle and superbly sung Norina in a stylish production of Donizetti’s “Don Pasquale.”

Best of all — a revelation, really — was a 1977 production of Bellini’s retelling of the Romeo and Juliet story, “I Capuleti e i Montecchi,” then a little-known and overlooked opera. Ms. Sills brought both girlish whimsy and tragic stature to her overwhelming portrayal of Giulietta. Singing Romeo was the plush-toned mezzo- soprano Tatiana Troyanos, in my first time hearing this remarkable artist.

There was something wonderfully American about Ms. Sills’s no-nonsense approach to singing. Her passagework was accurate and honestly executed; words came through clearly. Yet, while honoring the score, she sang with intensity and rich, though never maudlin, expressivity.

She was a total product of American training and proud of it. When she made her debut in 1969 at the most scared of all Italian opera houses, La Scala in Milan, in Rossini’s “Siege of Corinth,” it was practically an all-American affair. The other leads were Marilyn Horne and Justino Diaz (a Puerto Rico-born American); Thomas Schippers conducted. The critic at La Stampa commented that “American interpreters of Rossini brought bel canto again to La Scala.”

Ms. Sills’s Metropolitan Opera debut came shockingly late in her career. For years the company had been headed by the Austrian-born Rudolf Bing — later Sir Rudolf Bing — who barely disguised his patronizing attitude toward American singers. So it was sweet justice that she ended her influential career in arts administration as the chairwoman of the Met’s board.

When she announced her retirement in 2005 from administration and even from fund-raising, except for some charity work, I met with her at her elegant apartment overlooking Central Park for an interview. After my questions were answered and the tape recorder was turned off, she said that during her career she had tried to be careful about not fraternizing with critics. But now she was out of the business, she said. “So why don’t you and I just have lunch sometime, just for fun?” she asked.

A few months later we did. We met at Fiorello’s, across from Lincoln Center, where a table had a special plaque reading “Reserved for Beverly Sills,” for whenever she wanted it. Over lunch, we talked not as critic and diva but as two veteran opera buffs, sharing enthusiasms and gossip.

During the lunch, two middle-aged women stopped by our table. One asked Ms. Sills, “Are you who I think you are?”

Ms. Sills smiled at her warmly and said, “I hope so.”