The popular conception is that Abraham Lincoln single-handedly led the Union to victory, but Fergus Bordewich makes the case that four members of Congress—Thaddeus Stevens, Pitt Fessenden, Ben Wade, and the pro-slavery Clement Vallandigham—shaped one of the most consequential periods in American history. From reinventing the nation's financial system to pushing Lincoln to emancipate the slaves to the planning for Reconstruction, Congress took drastic measures to defeat the Confederacy, laying the foundation for a strong central government that came fully into being in the 20th century.