Annette Gordon-Reed made history in 1997, when her book Thomas Jefferson and Sally Hemings: An American Controversy argued persuasively that Jefferson had fathered children with Hemings. DNA evidence proved her right the following year, and now she's returned with The Hemingses of Monticello, an examination of Sally Hemings' family. Hemings was actually the half-sister of Jefferson's wife, Martha Wayles; Wayles' father had an affair with Hemings' mother after his own wife died. Gordon-Reed tells Newsweek that her background in law helped her make sense of Jefferson's life. "The first thing you learn in law school," she says, "is people are crazy." [Newsweek]