Schlesinger suffered a heart attack while dining out with family members Wednesday night in Manhattan, his son Stephen Schlesinger said. He was taken to New York Downtown Hospital, where he died.
"(He had) enormous stamina and a kind of energy and drive which most people don't have, and it kept him going, all the way through his final hours," Stephen Schlesinger said early Thursday morning, hours after his father's death. "He never stopped writing, he never stopped participating in public affairs, he never stopped having his views about politics and his love of this nation."
Schlesinger was among the most famous historians of his time, and was widely respected as learned and readable, with a panoramic vision of American culture and politics. He received a National Book Award for "Robert Kennedy and His Times" and both a National Book Award and a Pulitzer for "A Thousand Days," his memoir/chronicle of President John F. Kennedy's administration. He also won a Pulitzer, in 1946, for "The Age of Jackson," his landmark chronicle of Andrew Jackson's administration.
"He served his president, he served his country, and history will speak very well of him. We all should have history speak so well of us," Joe Cerrell, a Democratic political consultant who worked with Schlesinger in the Kennedy White House, told CBS Radio News' Charles White.
With his bow ties and horn-rimmed glasses, Schlesinger seemed the very image of a reserved, tweedy scholar. He was also an assured member of the so-called Eastern elite.
Cerrell described him as "bright. He was very well respected and not one of these pushy, aggressive types. A little more academic, which of course is what he was."
He was a longtime confidant of the Kennedys, a fellow Harvard man who served in President Kennedy's administration and was often accused of idealizing the family, especially not mentioning the president's extramarital affairs.
"At no point in my experience did his preoccupation with women — apart from (his daughter) Caroline crawling around the Oval Office — interfere with his conduct of the public business," Schlesinger later wrote.
Liberalism declined in his lifetime to the point where politicians feared using the word, but Schlesinger's opinions remained liberal, and influential, whether old ones on the "imperial presidency," or newer ones on the Iraq war. For historians and Democratic officials, he was a kind of professor emeritus, valued for his professional knowledge and for his personal past.
A native of Columbus, Ohio, and the son of a prominent historian, he was born Arthur Bancroft Schlesinger, Jr., but later gave himself his father's middle name, Meier. Family friends included James Thurber, historian Charles A. Beard and future Supreme Court justice Felix Frankfurter.