African Americans began a half-century exodus from the South during the First World War. A series of economic jolts in the middle of the decade, including floods and crop failures, left thousands of black sharecroppers and tenant farmers destitute and homeless. At the same time, the war severely curtailed the number of immigrants arriving from Europe, and a labor shortage in northern industrial cities opened employment opportunities. In 1916 the idea that the North offered a better way of life spread like wildfire through the states of the former Confederacy, and many white southerners became alarmed at the flight of cheap labor from their states. In 1916 the Pennsylvania Railroad hired 10,000 people from Georgia and Florida alone. Between 1910 and 1920 northern and western states registered an increase of 330,000 African American inhabitants. The migration opened industrial employment to blacks, staved off a labor shortage during the war...