By May 1968, Brodie was committed to writing the Jefferson biography. She understood that it could not be a full account. The study of Jefferson had become a virtual career for several living historians. For instance, Dumas Malone was in the process of completing a six-volume biography of Jefferson, which won the Pulitzer Prize in 1975. Brodie decided to concentrate on a biography of “the private man”. She decided to build on several recently published articles on the historical controversy describing a reported sexual relationship between Jefferson and Sally Hemings, a quadroon slave said to be the half-sister of his late wife. The topic was timely during a period of increased national interest in race, sex, and presidential hypocrisy. Brodie had personal reasons as well, having discovered that her husband had been conducting an extramarital affair."[I]n weighing her husband's indiscretion against the overwhelmingly positive aspects of their relationship, Fawn concluded that their marriage of some thirty years was worth preserving." Jefferson reminded Brodie of her father: orderly, self-controlled, and chronically in debt. .
