Final answer:
The deployment of African American regiments in the Union Army was a significant success, as it helped reframe the Civil War as a fight for freedom and emancipation, setting the stage for future civil rights advancements.
Step-by-step explanation:
One significant success of the Civil War for African Americans was the shift in the war's focus to emancipation and freedom. This was epitomized by the formation and deployment of African American regiments in the Union Army. Frederick Douglass, a key abolitionist, powerfully articulated the African American wartime experience, urging that those seeking freedom must fight for it. His rallying cry, emphasizing the role black men should play in securing their liberty, was a pivotal call to arms.
Further evidence of this success comes from President Abraham Lincoln's correspondence with General Ulysses S. Grant. Despite initially being a war to preserve the Union, Lincoln's views evolved, acknowledging the crucial role that African American soldiers played in achieving Union victory. His letter to Grant emphasized that leveraging the black soldiers as a resource would significantly aid the Union effort and hasten an end to the conflict.
The warrant for this claim is that the participation of African American soldiers was instrumental in redefining the Civil War, making it a conflict not only about preserving the Union but also about securing civil rights and equality. The impact extended beyond the war front, contributing to the post-war drive for greater civil rights, as African American experience and service accentuated the disparities between the nation’s founding ideals and the reality of racial inequality.