William Henry Seward was one of the most important Americans of the nineteenth century. Progressive governor of New York and outspoken U.S. senator, he was the odds-on favorite to win the 1860 Republican nomination for president. As secretary of state and Lincoln's closest adviser during the Civil War, Seward not only managed foreign affairs but had a substantial role in military, political, and personnel matters. Acclaimed biographer Walter Stahr sheds new light on this complex and central figure in the first full life biography of Seward in more than forty years.