What were the causes and effects of the union accepting african americans as soldiers?

The primary cause of the union accepting African Americans as soldiers was that they needed as much man power as they could get in the fight against the South. The result was that the African Americans fought extremely well, due in part to the fact that they believed so strongly in the North's cause.

Contributing factors  leading  to the harlem renaissance were the great migration of african americans to northern cities, which concentratedambitious  people in places where they could encourage each  other, and the first world war, which had created new industrial work opportunities for tens of thousands of people.