As agriculture was mechanized, reducing the need for farm labor, many blacks left Amite County during the first half of the 20th century in two waves of the Great Migration. In the first wave, before World War II, many moved north to Chicago and other industrial cities of the Midwest. In the second wave, they moved to the West Coast, where the burgeoning defense industry created jobs before, during, and after the war. From 1940 to 1960, the county population declined by 29%, as can be seen on the census tables below. Some rural whites also left the county for industrialized cities.