Imagine you are young John Quincy Adams. Your ancestors include a dozen kings of England and of France, William the Conqueror and Charlemagne among them. Your parents are educated and ambitious, and you are their eldest son. You think you might be a bit driven? Harlow Giles Unger tells the story of John Quincy Adams in a fast-moving, intimate, and wonderfully entertaining biography. Unger is aided by the fact that John Quincy kept a diary, more or less faithfully, from the ages of 10 to 80. He also was an inveterate writer of letters, most of which seem to have …