"So you're the little lady who started the war," Abraham Lincoln is rumored to have said when he met the author of Uncle Tom's Cabin on the eve of the Emancipation Proclamation. Harriet Beecher Stowe's groundbreaking novel forced an ambivalent North to confront the atrocities of slavery, yet her accomplishment was just one of many of the Beechers, the most eminent American family of the nineteenth century. In this intimate account, historian Philip...