The Great Migration was the movement out of the South of the United States by millions of African-Americans during the first half of the 20th century. They left the rural South and migrate towards the urban Northeast, Midwest, and West of the country.
The pace of this accelerated with the outbreak of World War I because the industrial parts of the United States needed more workforce in the urban areas.
The civil war would have occurred anyways. There was serious underpinning dismay in society of that time period. And we fully do not understand what the misgivings were of that time.
