Over a long career spent on both sides of the Iron Curtain, Ms. Vishnevskaya fulfilled a variety of responsibilities, to art, to her family and to history. She and her husband were regarded as symbols of the struggle for personal and cultural freedom and against Soviet repression.
Each famed in their native country, they were exiled after they took in Nobel Prize-winning author Alexander I. Solzhenitsyn at a time when he was in deep disfavor with the Soviets.
During their time in the United States — and particularly in Washington, where her husband was a towering presence as musical director of the National Symphony Orchestra for 17 years — she sometimes was identified as Mrs. Mstislav Rostropovich.
But in Russia, before exile in 1974, Ms. Vishnevskaya had achieved fame even beyond that of her celebrated cellist husband. At the height of her vocal power in the 1950s and ’60s, Ms. Vishnevskaya was, The Washington Post once wrote with little exaggeration, the musical Empress of all the Russias.
Amid the deprivations experienced in Leningrad in World War II, a time in which she nearly starved, Ms. Vishnevskaya began her career singing in operettas.
In 1952, she won a national competition to train with the Bolshoi Opera Company, the leading opera company in the Soviet Union.
By the next season, she was the company’s reigning soprano. One of her first parts, Tatiana in Tchaikovsky’s “Eugene Onegin,” would remain a signature role for her.
Some of the most eminent composers of the 20th century wrote for her. British composer Benjamin Britten wrote the soprano part of his masterpiece “War Requiem” for her. Dmitri Shostakovich dedicated to her his “Seven Romances.”
On infrequent trips permitted by the Soviets, Ms. Vishnevskaya sang in the most prestigious opera houses in the world, including London’s Royal Opera House in Covent Garden, Milan’s La Scala and New York’s Metropolitan Opera. She appeared at the Met for the first time in 1961 in the title role of Verdi’s “Aida.”
(Her appearances at the Met, critic Raymond Ericson once wrote in the New York Times, were like comets — “sudden, infrequent, capable of lighting up the sky.”)
Her repertoire spanned the Italian, French and English canon, but she was most associated with Russian composers such as Tchaikovsky, Prokofiev, Rimsky-Korsakov and Shostakovich. Beyond its exquisite tone, and deep vibrato, admirers said, her voice possessed an unmistakably Russian intensity.
Ms. Vishnevskaya held the rank of “people’s artist of the Soviet Union” and was one of the most renowned musicians in the country, at one point batting away the advances of then-Prime Minister Nikolai A. Bulganin.