  Migrations within the United States were by far the most significant of the relocations. And the movements greatly accelerated over the decades as the nineteenth century gave way to the twentieth and the U.S. American economy was undergoing transformation into an industrial giant and international power as a consequence of meeting the needs of production to support the country’s participation in the First World War and other developments. In the North, Northeast, and West of the country this industrialization created historic demands for workers and, subsequently, historic opportunities for work. Meanwhile, in the South rapidly increasing mechanization in agriculture and subsequent decreasing reliance on the labor of nearly-enslaved, hyper-exploited Negro tenant farmers and workers, and increasing industrialization in the region, left the greater majority of Black people in dire straits. These developments, combined with hopes for life unrestricted by racial segregation enforced by brutal violence, by lynchings especially, exerted additional pull-and-push forces that prompted hundreds of thousands to join in the migrations to the country’s industrial centers.