Ms. Ruzickova, shown here in Prague in 2016, was one of the world’s preeminent harpsichordists and a Holocaust survivor. (Katerina Suldova/AP)

Zuzana Ruzickova, a Czech survivor of the Nazi concentration camps who rediscovered beauty in life through the music of J.S. Bach, a canon to which she dedicated her life as one of the world’s premier harpsichordists, died Sept. 27 at a hospital in Prague. She was 90.

The cause was pneumonia and exhaustion, said a cousin, Frank Vogl.

Ms. Ruzickova achieved international renown as the first soloist in history to record Bach’s complete keyboard works. The collection, originally made for the French label Erato from 1965 to 1974, filled 35 records and was rereleased last year by Warner Classics in advance of her 90th birthday.

A documentary about her life, "Zuzana: Music Is Life," directed by the Bethesda, Md.-based Harriet Gordon Getzels and Peter Getzels, was released earlier this year.

“I needed Bach,” said Ms. Ruzickova, shown here in 1969. “His music is above human suffering.” (Alexandr Janovsky/CTK via AP)

Ms. Ruzickova trained initially as a pianist but became best known as a virtuoso of the harpsichord, a principal instrument for which Bach composed, and one whose sound she helped revive in modern concert halls.

Her devotion to the German composer, whose life spanned the 17th and 18th centuries, was deep and almost primal. She said she had loved his music since she was an 8-year-old in prewar Czechoslovakia and credited Bach’s restrained intensity with helping her endure the horrors and memory of the Holocaust.

In the Baroque perfection of his preludes, fugues, toccatas and fantasias, she said, one could find the order that is not always visible in the melee of human life.

“I needed Bach,” Ms. Ruzickova told BBC Music Magazine. “Unlike Beethoven, who shakes his fist at the heavens, Bach could help me after everything I’d been through. His music is above human suffering.”

Zuzana Ruzickova was born Jan. 14, 1927, in the Czech city of Pilsen. Her parents, who were Jewish, ran a general store and encouraged her love of music. She received her first piano lessons as a gift when she recovered from a childhood bout of tuberculosis.

Ms. Ruzickova was 12 when the Germans invaded and occupied Czechoslovakia. She and her parents were interned in Terezin, the concentration camp-ghetto located outside of Prague and also known as Theresienstadt, where her father perished.

From there, Ms. Ruzickova and her mother were deported to Auschwitz, the Nazi death camp in occupied Poland. Narrowly avoiding the gas chamber, they were selected for slave labor in Hamburg before ultimately being liberated by the British from Bergen-Belsen in Germany.

Music, Ms. Ruzickova said, was her salvation. On the cattle car en route to Auschwitz, she scribbled several bars from Bach's English Suite No. 5 in E minor on a piece of paper. "I wanted to have a piece of Bach with me as a sort of talisman because I didn't know what was awaiting us," she told the BBC.

In the camps, she sang passages from operas to fellow inmates as a means of psychological escape.

Upon her return to Czechoslovakia after the war, Ms. Ruzickova attempted to resume her musical studies, but slave labor had badly injured her hands. Her physicals wounds, combined with her emotional ones and her lost years of study, led teachers to tell her that she could no longer hope for a career in music.

But she persisted and received a scholarship to the Prague music academy in 1948, her cousin said, the year Communists came to power in Czechoslovakia. Because she refused to join the Communist Party, the academy declined to award her the doctorate that her cousin said she had earned.

At the academy she met Viktor Kalabis, a Czech composer, whom she married in 1952. Poverty-stricken, they lived for a time with her mother in a small apartment and slept under the piano.

As Ms. Ruzickova’s musical talent blossomed, the Communist government allowed her to travel for concerts but collected a large portion of the foreign currency she received in payment. She said her husband persuaded her to perform in Germany — to show that Hitler had not succeeded in extinguishing German or European culture — where she won the ARD music competition in 1956.

The invitation from Erato to record Bach’s keyboard compositions brought her to the attention of classical music enthusiasts around the world.

"There's a sense of rightness to Zuzana Ruzickova's Bach that transcends fads and fashions and the deadening impact of scholarly dogma," music writer Rob Cowan observed in a 2017 review for Gramophone.

“Some might find it just a mite too stately, its persistent propensity for shifting colors and registrations intrusive,” he continued. “ ‘In your face’ is the appropriate modern phrase I suppose, but there isn’t a musical face in existence I’d rather confront than Bach’s and I thank Zuzana Ruzickova for this sublime close encounter.”

Ms. Ruzickova also was widely noted as an interpreter of Domenico Scarlatti, an Italian contemporary of Bach’s. After the Velvet Revolution ended Communist rule in Czechoslovakia in 1989, she received a professorship long denied to her and performed for the first time in the United States. She also lectured on her experiences in the Holocaust, her cousin said.

Ms. Ruzickova’s husband died in 2006, two years after she retired from the stage. She had no immediate survivors.

"Bach is very soothing," Ms. Ruzickova told the BBC last year. "You always feel in his music that God is present somehow. And that, of course, helps."