The Great Depression of the 1930s hit the county hard, decimating the agricultural sector. World War II brought an end to the depression. As the defense industry built up in major cities and on the West Coast, from 1940 to 1970, a total of more than 4.5 million blacks migrated from Texas, Louisiana, Mississippi and other southern states. They moved to the West Coast in the second wave of the Great Migration, attracted to new jobs in the expanding defense industry.