Upon his election to the presidency, Lincoln inherited a country in crisis. Even before the Confederacy’s secession, the United States Treasury had run out of money. But amid unprecedented troubles Lincoln saw opportunity—the chance to legislate in the centralizing spirit of the “more perfect union” that had first drawn him to politics. Roger Lowenstein reveals, through a financial lens, the largely untold story of how Lincoln used the urgency of the Civil War to transform a union of states into a united nation.