Many african americans during world war i could not find work at all. could not move to find work. found work in rural areas. found work in northern cities.

The answer is found work in northern cities.
Following the world war I, the industrial revolution keep spreading like wildfire in united states, Northern Cities became the center of the revolution in United States.
Many African American moved to northern cities in order to found job as factory workers, and tripled the North's African American population in about ten years after the war.

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