What was the impact of the war on south's african american population?

Down in the South, racism was horrible as it was. When the civil war broke out between the North and South it was game on. The Africans had the opportunity to leave and serve for the north. So the African Population in the South decreased for two reasons... one being that they left to go fight for their freedom and two because in some cases the South made their slaves do all the dirty work and fight front line in the hard battles.