Fou Ts’ong, a Chinese pianist known for his sensitive interpretations of Chopin, Debussy and Mozart, and whose letters from his father, a noted translator and writer, influenced a generation of Chinese readers, died on Monday at a hospital in London, where he had lived for many years. He was 86.

The cause was the coronavirus, said Patsy Toh, a pianist, who had been married to Mr. Fou since 1975.

In 1955, Mr. Fou became one of the first Chinese pianists to achieve global prominence when he took third place in the International Chopin Piano Competition in Warsaw, also winning a special prize for his performance of Chopin’s mazurkas.

Almost overnight, he became a national hero at home. To China’s nascent Communist-led government, Mr. Fou’s recognition in a well-known international competition was proof that the country could stand on its own artistically in the West. Chinese reporters flocked to interview Mr. Fou, while many others sought out his father, Fu Lei, a prominent translator of French literature, for advice on child-rearing.

But the authorities’ good will did not last long.

Two years later, Mao Zedong initiated the Anti-Rightist Campaign, during which hundreds of thousands of Chinese intellectuals, including Mr. Fu, were persecuted. Many were tortured and banished to labor camps. Mr. Fou, then studying at the Warsaw Conservatory in Poland, was made to return to China to undergo “rectification” for several months.

Not long after going back to Warsaw, Mr. Fou found himself in a quandary. Having witnessed the increasingly tumultuous political climate back home, he knew that if he returned to China upon graduation — as the government expected him to do — he would be expected to denounce his father, an unimaginable situation.

So in December 1958, Mr. Fou fled then-Communist Poland for London, where he claimed political asylum.

“About my leaving, I always felt full of regret and anguish,” he later recalled in an interview. So many intellectuals in China had suffered, he said, but he had escaped. “I felt uneasy, as if I owed something to all my friends,” he added.

After his defection to London, Mr. Fou maintained a written correspondence with his father in Shanghai — a special privilege that was said to have been personally approved by Zhou Enlai, the Chinese premier.

Then, in 1966, Mao unleashed the Cultural Revolution, a decade-long period of chaos that upended Chinese society. Militant Red Guards accused Mr. Fu, a prolific translator of writers like Balzac and Voltaire, of having “capitalistic” artistic taste, among other crimes. They humiliated and tortured the scholar and his wife for days until the couple, like many other Chinese, were driven to suicide. Mr. Fou, still in London, did not learn of his parents’ deaths until several months later.

In 1981, after China’s post-Mao government posthumously restored the reputations of Mr. Fou’s parents, a volume of letters written by his father, primarily to Mr. Fou, was published in China. Full of advice, encouragement, life teachings and stern paternal love, the book, “Fu Lei’s Family Letters,” became an instant best seller in China.

For many, the long disquisitions on music, art and life offered a welcome contrast to the Cultural Revolution years, which saw sons turn against fathers, students against teachers and neighbors against neighbors — all in the name of politics.

“If you imagine the environment we grew up with, it was very rigid,” said Xibai Xu, a political analyst who first read the letters in middle school in Beijing. He added, “So when you read ‘Fu Lei’s Family Letters,’ you realized how a decent human life could be — a life that is very delicate and artistic, with real human emotions and not just ideology.”

Besides influencing a generation of Chinese, Mr. Fu’s words resonated long after his death with the person for whom they were originally intended.

“My father had a saying that ‘First you must be a person, then an artist, and then a musician, and only then can you be a pianist,’” Mr. Fou once recalled in an interview. “Even now, I believe in this order — that it should be this way and that I am this way.”

Fou Ts’ong was born on March 10, 1934, in Shanghai. His father, in addition to being a translator, was an art critic and a curator. His mother, Zhu Meifu, was a secretary to her husband.

Under the strict supervision of their father, Mr. Fou and his brother, Fu Min, were educated in the classical Chinese tradition, and they grew up surrounded by both Western and Chinese cultural influences. As a child, Mr. Fou studied art, philosophy and music, frequently making use of his father’s phonograph and extensive record collection.

A lover of classical music from a young age, Mr. Fou began taking piano lessons when he was 7. He later studied under a number of teachers, including Mario Paci, the Italian conductor of the Shanghai Philharmonic.

But the chaos of wartime China prevented the young pianist from receiving a systematic musical education. In 1948, Mr. Fou, then in his teens, moved with his family to the southwestern province of Yunnan, where he went through what he described as a rebellious period. It was only after returning to Shanghai several years later that he began to dedicate himself in earnest to the piano.

In 1952, Mr. Fou made his first stage appearance, playing Beethoven’s “Emperor” Concerto with the Shanghai Symphony Orchestra. The concert caught the attention of officials in Beijing, who selected the young pianist to compete and tour in Eastern Europe, Mr. Fou’s first trip abroad.

Soon, Mr. Fou moved to Poland, where he studied at the Warsaw Conservatory on a scholarship. To prepare for the fifth Chopin Competition in Warsaw in 1955, he practiced so diligently that he hurt his fingers and was nearly cut from the first round of competition.

After the deaths of his parents in 1966, Mr. Fou stayed abroad, rising to become a renowned concert pianist on the international circuit. Though he was best known for his interpretations of Chopin, he also received acclaim for his performances of works by Haydn, Mozart, Schubert and Debussy. In a review of a 1987 recital in New York, the critic Bernard Holland wrote in The New York Times of Mr. Fou’s “sensitive ear for color” and “elusive gift of melody.”

“We should hear Mr. Fou more often,” Mr. Holland wrote. “He is an artist who uses his considerable pianistic gifts in pursuit of musical goals and not for show.”

In 1979, after Mao’s death and the end of the Cultural Revolution, Mr. Fou was granted permission to return to China for the first time in more than two decades, reuniting with his brother to hold a memorial service for their parents.

On subsequent visits, Mr. Fou gave performances and lectures; he became known to many Chinese as the “Piano Poet” for his lyrical musical interpretations. Later versions of “Fu Lei’s Family Letters” were updated to include some of Mr. Fou’s letters to his father.

Mr. Fou’s death came at a time of resurgent nationalism in China. On Chinese social media, some ultranationalist commentators called him a traitor to the country for having defected decades ago, echoing similar accusations that Mr. Fou faced in the 1950s not long after settling in London.

“What would I tell them? There was nothing to say,” Mr. Fou once said of such critics in an interview. “It’s not that I was longing for the West.”

“I was choosing freedom,” he added. “It was not an easy situation. There was no other choice.”

Many other Chinese honored his memory, including well-known pianists like Li Yundi as well as Lang Lang, who called Mr. Fou “a clear stream in the world of classical music and a beacon of light in our spirit.”

“Fou Ts’ong’s legacy was to show people and musicians the importance of integrity, character and music beyond technique,” said Jindong Cai, a conductor and the director of the U.S.-China Music Institute at Bard College Conservatory of Music.

Mr. Fou’s first marriage, to Zamira Menuhin, daughter of the prominent violinist Yehudi Menuhin, ended in divorce, as did a brief marriage to Hijong Hyun. In addition to Ms. Toh, Mr. Fou is survived by a son from his first marriage, Lin Xiao; a son from his marriage to Ms. Toh, Lin Yun; and his brother, Mr. Fu.

Mr. Fou remained passionately devoted to music in his later years, playing piano for hours every day even as his fingers grew frail. It was a love that he invoked often in interviews, alongside nuggets of wisdom from his father.

“When I was very young, I wrote to my father from Poland that I was sad and lonely,” he once recalled. “He wrote back: ‘You could never be lonely. Don’t you think you are living with the greatest souls of the history of mankind all the time?’”

“Now that’s how I feel, always,” Mr. Fou said.

Amy Chang Chien contributed reporting.