Twelve Days: How the Union Nearly Lost Washington in the First Days of the Civil War by Tony Silber
In the popular literature and scholarship of the Civil War, the days immediately after the surrender at Fort Sumter are overshadowed by the great battles and seismic changes in American life that followed. The twelve days that began with the federal evacuation of the fort and ended with the arrival of the New York Seventh Militia Regiment in Washington were critically important. The nation’s capital never again came so close to being captured by the Confederates.-Goodreads