Racial segregation was strictly enforced by Jim Crow Laws before WWII. African Americans also had no voting rights, even men. African Americans that used "White Only" services were beat severely or killed.
Many African Americans had mixed feelings to help the war efforts over seas for freedom when back home they weren't receiving equal rights.
ADDSCO Shipyard hired unskilled African Americans for low paying jobs. Many white Americans were furious to have to work with the unskilled workers. The white workers then rioted and beat black workers.