Thanks in part to the rapid mechanization of cotton production in the early 1940s, which ultimately threw millions of farm laborers out of work, and in part to the opening up of industrial employment in the North during the wartime boom, roughly a million blacks (along with even more whites) moved from the South during the 1940s. Another 1.5 million Negroes left the South in the 1950s. This was a massive migration in so short a time—one of the most significant demographic shifts in American history—and it was often agonizingly stressful.
