From one of our most acclaimed new biographers--the first full life of the leader of Lincoln's "team of rivals" to appear in more than forty years. William Henry Seward was one of the most important Americans of the nineteenth century. Progressive governor of New York and outspoken US 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...