Beverly Sills was just as comfortable singing with the Muppets as the Metropolitan Opera. Her ability to sing a complex operatic role one night and a duet full of one-liners with Carol Burnett another made her an artistic icon who helped popularize opera. America’s queen of opera was silenced this week at the age of 78.

With her red hair, seemingly omnipresent smile and melodious voice, Ms. Sills lived the storybook American success story peppered with tragedy and determination. Born Belle Miriam Silverman in Brooklyn to Jewish immigrant parents, she began her stage career at age 4. At the suggestion of a family friend, her name was changed to Beverly Sills at 7 when she began singing arias she had phonetically memorized from her mother’s record albums.

Although she began voice lessons at the age of 9, she never attended a conservatory and did not travel to Europe to hone her operatic skills, unusual for opera singers in the mid-20th century.

She auditioned eight times before landing a role at the New York City Opera, which became her artistic home for 25 years. Many critics call her best role her 1966 City Opera performance as Cleopatra in Handel’s “Julius Caesar.”

The performance came after she and her husband, newspaper heir, Peter Greenough, learned that their daughter, then almost 2, was deaf and that their 6-month old son was severely mentally disabled.

“After I came back [from taking time off with her children], I talked back. I stopped caring what anyone else thought,” she said in a 1969 Newsweek interview. “I felt if I could survive my grief, I could survive anything,” she said. “Onstage I was uninhibited, and I began to have a good time.”

Ms. Sills did not make her debut at the Metropolitan Opera, America’s premier opera, until 1975, when her voice was already in decline. She left the stage in 1980.

She then became general director of the City Opera, which was known as the “people’s opera company” compared to the better-known Met. It became the first American opera company to use subtitles, projecting an English translation on a screen above the stage, and Ms. Sills dropped ticket prices to encourage new audiences.

Despite her operatic success, Ms. Sills is likely better known to younger generations as the wisecracking guest host of the “Tonight Show” or the bubbly diva who explained opera in simple terms as a host for the “Live from Lincoln Center” television shows.

Ms. Sills’ voice has been quieted, but her spirit couldn’t be.