He was America's jaunty celebrity historian. Schlesinger, a bow-tied liberal centrist, didn't just record history — he helped make it. He published influential studies of crucial presidencies, notably Andrew Jackson's and Franklin D. Roosevelt's. And he wrote about John F. Kennedy from close range, as a White House "special assistant" who advised on policy. His notes from those years became the basis for A Thousand Days: John F. Kennedy in the White House, which won him the second of two Pulitzer Prizes.