The most famous and well-known African American unit during the Civil War was the 54th Massachusetts regiment. The Most Famous Civil War Black Regiment.Reconstruction and the Civil War ended slavery, altered relationships between the states and the federal government, and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities. The North’s greater manpower and industrial resources, the leadership of Abraham Lincoln and others, and the decision to emancipate slaves eventually led to the Union military victory over the Confederacy in the devastating Civil War.