An enlightening narrative exploring an oft-overlooked aspect of the sixteenth president's life, An American Marriage reveals the tragic story of Abraham Lincoln’s marriage to Mary Todd. Abraham Lincoln was apparently one of those men who regarded “connubial bliss” as an untenable fantasy. During the Civil War, he pardoned a Union soldier who had deserted the army to return home to wed his sweetheart. As the president signed a document sparing the soldier's life, Lincoln said: “I want to punish the young man—probably in less than a year he will wish I had withheld the...