Emeritus Sterling Professor of History Peter Gay — described as “the ultimate homme de lettres” — died Tuesday at his home in Manhattan. He was 91 years old.

The cause of death was “old age,” his stepdaughter Elizabeth Glazer told the Associated Press.

Born in Berlin in 1923, Gay, along with his family, escaped from Nazi Germany during his teenage years. Although he and his parents were identified by the Nazis as Jews — his father’s business was one of thousands of Jewish establishments attacked during Kristallnacht in 1938 — the family did not identify with the religion, the New York Times reported. The family fled first to Havana, Cuba, where Gay taught himself English by reading magazines and listening to broadcasts, before arriving to the United States in 1941.

He went on to study Jewish history and write about Nazi Germany, among many other topics, and he eventually became one of the English language’s most elegant writers. As history professor Jay Winter, who learned from Gay as an undergraduate, put it, he was “a man who writes like an angel.”

“The world of ideas was an elegant idea; [Gay] thought it should be expressed in elegant prose,” said Jon Butler, a former Yale history professor who overlapped with Gay in the department for nearly a decade. “There were very few historians who could or would equal his achievements.”

Gay, born Peter Joachim Fröhlich, wrote prolifically on topics as wide-ranging as Mozart, Freud and the Enlightenment. In his decades-long career, he published nearly 30 volumes, writing at a rate his colleagues agreed is astonishingly fast. His book “The Enlightenment: An Interpretation. The Rise of Modern Paganism,” considered the quintessential text on the period, won the National Book Award in 1967, and in 2003, Gay was honored with a lifetime achievement award from the American Historical Association.

History professor David Sorkin, a scholar of Jewish history whose work departs from Gay’s, described him as “tremendously influential, tremendously admired.”

“He was a wonderful historian, an outstanding stylist,” Sorkin said. “Even if you disagree with him, you have to admire what he did.”

Focused largely on Western Europe, Gay also delved deep into the field of psychology, even completing all the coursework required for psychoanalyst training in order to better understand the human psyche and its role in history. Gay also wrote a well-received biography of Sigmund Freud.

After over two decades of teaching at Yale, Gay retired in 1993, one of the final years during which Yale still mandated faculty retirement after the age of 70. Butler said the scholar would have much preferred to continue stay on.

Still, Gay’s departure from Yale hardly slowed his career. In 1999, he became the founding director of the Dorothy and Lewis B. Cullman Center for Scholars and Writers, a global fellowship program housed within the New York Public Library. He filled that role until 2003 while also continuing his own scholarship. Since 1993, Gay has continued to publish, including several volumes of his five-part series “The Bourgeois Experience: Victoria to Freud” and his autobiography, “My German Question: Growing Up in Nazi Berlin.”

Even in his later years, when his health began to decline, Gay’s mind remained sharp, friends said. His most recent book, “Why the Romantics Matter,” was published in January, and University of Illinois history professor Mark Micale, a former graduate student advisee of Gay’s who compiled the footnotes for the volume, said there was “no loss of literary grace at all.” According to Yale history professor John Merriman, a close personal friend, Gay had another book under contract when he died this week.

But beyond his intellectual contributions, those who knew Gay also described him as a person of sophistication, warmth and personal elegance. They also remembered him for his impressive art collection and personal library, his penchant for tuna salad sandwiches and his photographic memory. Several recalled the graduate student tutorials he hosted in his home in Hamden and the many meals eaten with him at Yorkside Pizza Restaurant.

“He just cared about people, not just vaguely in the abstract but on a day-to-day basis,” said Merriman, who asked Gay to be a groomsmen in his wedding. “He was one of my heroes and one of my best friends.”